AIS Events

Zone Dwell Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 10:18 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 54m
Data Points: 8 AIS positions
Period: 2026-10-23T10:18:05+00:00 to 2026-10-23T15:12:09+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 294.1000000000000227373675443232059478759765625,
    "points_in_zone": 8,
    "first_point": {
        "ts": "2026-10-23T10:18:05+00:00",
        "lat": 46.619761699999997972554410807788372039794921875,
        "lon": 142.899484999999998535713530145585536956787109375
    },
    "last_point": {
        "ts": "2026-10-23T15:12:09+00:00",
        "lat": 46.619765000000001009539118967950344085693359375,
        "lon": 142.899488300000001572698238305747509002685546875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 09:04 UTC 75.0% ▼

Duration: 6h 21m
Radius: 50 meters
Data Points: 46 AIS positions
Centroid: 46.5364, 142.9391
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 49.60000000000000142108547152020037174224853515625,
    "duration_minutes": 381,
    "points": 46,
    "centroid": {
        "lat": 46.5363828282608693598376703448593616485595703125,
        "lon": 142.939067141304320784911396913230419158935546875
    },
    "bbox": {
        "min_lat": 46.5361199999999968213160173036158084869384765625,
        "min_lon": 142.938573300000001609078026376664638519287109375,
        "max_lat": 46.53659669999999692890924052335321903228759765625,
        "max_lon": 142.93959000000000969521352089941501617431640625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 09:04 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 21m
Data Points: 46 AIS positions
Period: 2026-10-23T09:04:50+00:00 to 2026-10-23T15:25:49+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 381,
    "points_in_zone": 46,
    "first_point": {
        "ts": "2026-10-23T09:04:50+00:00",
        "lat": 46.5361199999999968213160173036158084869384765625,
        "lon": 142.93959000000000969521352089941501617431640625
    },
    "last_point": {
        "ts": "2026-10-23T15:25:49+00:00",
        "lat": 46.53631169999999883657437749207019805908203125,
        "lon": 142.939093299999996133919921703636646270751953125
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 08:24 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 26m
Data Points: 8 AIS positions
Period: 2026-10-23T08:33:15+00:00 to 2026-10-23T15:00:12+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 386.8999999999999772626324556767940521240234375,
    "points_in_zone": 8,
    "first_point": {
        "ts": "2026-10-23T08:33:15+00:00",
        "lat": 46.61975830000000087238731794059276580810546875,
        "lon": 142.899483300000014196484698913991451263427734375
    },
    "last_point": {
        "ts": "2026-10-23T15:00:12+00:00",
        "lat": 46.6197767000000027337591745890676975250244140625,
        "lon": 142.899484999999998535713530145585536956787109375
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach GALAXY (IMO: 9826902, MMSI: 461000329)

Oct 23, 2026 08:19 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 17m
Data Points: 16 AIS positions
Period: 2026-10-23T08:51:32+00:00 to 2026-10-23T15:08:40+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 377.1000000000000227373675443232059478759765625,
    "points_in_zone": 16,
    "first_point": {
        "ts": "2026-10-23T08:51:32+00:00",
        "lat": 46.2407333000000022593667381443083286285400390625,
        "lon": 142.77244830000000774816726334393024444580078125
    },
    "last_point": {
        "ts": "2026-10-23T15:08:40+00:00",
        "lat": 46.27934830000000232530510402284562587738037109375,
        "lon": 142.77329670000000305662979371845722198486328125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 08:07 UTC 75.0% ▼

Duration: 6h 36m
Radius: 59 meters
Data Points: 46 AIS positions
Centroid: 46.5364, 142.9391
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 59.2999999999999971578290569595992565155029296875,
    "duration_minutes": 396,
    "points": 46,
    "centroid": {
        "lat": 46.5363774652173987078640493564307689666748046875,
        "lon": 142.9390804760869286837987601757049560546875
    },
    "bbox": {
        "min_lat": 46.53606500000000067984728957526385784149169921875,
        "min_lon": 142.938573300000001609078026376664638519287109375,
        "max_lat": 46.53659669999999692890924052335321903228759765625,
        "max_lon": 142.9397066999999879044480621814727783203125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 08:07 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 36m
Data Points: 46 AIS positions
Period: 2026-10-23T08:43:50+00:00 to 2026-10-23T15:19:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 396,
    "points_in_zone": 46,
    "first_point": {
        "ts": "2026-10-23T08:43:50+00:00",
        "lat": 46.53606500000000067984728957526385784149169921875,
        "lon": 142.9397066999999879044480621814727783203125
    },
    "last_point": {
        "ts": "2026-10-23T15:19:50+00:00",
        "lat": 46.53629829999999856227077543735504150390625,
        "lon": 142.93919829999998682978912256658077239990234375
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 08:06 UTC 72/100 ▼

Vessel A: SOLARIS (SOLARIS) OMAN

Vessel B: IMO 9183817 (BUKHTA NAGAEVA) RUSSIA

Minimum Distance: 68 meters
Average Distance: 155 meters
Duration: 40 minutes
Period: 2026-10-23T08:06:06+00:00 to 2026-10-23T08:46:08+00:00
Vessel A Avg Speed: 0.1 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 72/100

Moderate-confidence STS candidate. Two tankers (SOLARIS and BUKHTA NAGAEVA) maintained close proximity (min 68m, avg 155m) for 40 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 68m, avg 155m
Duration	5/25	Duration 40 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	12/15	Distance variance ±49m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T09:45:03.770125+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 461000248,
        "imo": 9333436,
        "name": "SOLARIS",
        "flag": "OMAN"
    },
    "vessel_b": {
        "mmsi": 273219140,
        "imo": 9183817,
        "name": "BUKHTA NAGAEVA",
        "flag": "RUSSIA"
    },
    "min_distance_m": 68.400000000000005684341886080801486968994140625,
    "avg_distance_m": 154.900000000000005684341886080801486968994140625,
    "distance_consistency_m": 49.39999999999999857891452847979962825775146484375,
    "duration_minutes": 40,
    "overlap_duration_s": 2402,
    "speed_a_avg": 0.08000000000000000166533453693773481063544750213623046875,
    "speed_a_std": 0.08000000000000000166533453693773481063544750213623046875,
    "speed_b_avg": 0.059999999999999997779553950749686919152736663818359375,
    "speed_b_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.08000000000000000166533453693773481063544750213623046875,
            "max_sog": 0.200000000000000011102230246251565404236316680908203125
        },
        "vessel_b": {
            "avg_sog": 0.059999999999999997779553950749686919152736663818359375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        }
    },
    "time_window": {
        "start": "2026-10-23T08:06:06+00:00",
        "end": "2026-10-23T08:46:08+00:00"
    },
    "points_count": {
        "vessel_a": 5,
        "vessel_b": 5
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 72,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 68m, avg 155m"
            },
            "duration": {
                "score": 5,
                "max": 25,
                "detail": "Duration 40 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 12,
                "max": 15,
                "detail": "Distance variance \u00b149m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "Moderate-confidence STS candidate. Two tankers (SOLARIS and BUKHTA NAGAEVA) maintained close proximity (min 68m, avg 155m) for 40 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.6499450000000024374458007514476776123046875,
            "lon": 142.54302999999998746716300956904888153076171875
        },
        "time_window": {
            "start_ts": "2026-10-23T08:06:06+00:00",
            "end_ts": "2026-10-23T08:46:08+00:00"
        },
        "searched_at": "2026-10-23T09:45:03.770125+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 08:05 UTC 75.0% ▼

Duration: 2h 49m
Radius: 72 meters
Data Points: 16 AIS positions
Centroid: 46.6922, 142.5761
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 72.099999999999994315658113919198513031005859375,
    "duration_minutes": 169.80000000000001136868377216160297393798828125,
    "points": 16,
    "centroid": {
        "lat": 46.6922457187500157260728883557021617889404296875,
        "lon": 142.576121349999965559618431143462657928466796875
    },
    "bbox": {
        "min_lat": 46.69163999999999958845364744774997234344482421875,
        "min_lon": 142.57553999999998950443114154040813446044921875,
        "max_lat": 46.6926150000000035333869163878262042999267578125,
        "max_lon": 142.576448300000009794530342333018779754638671875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 08:05 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 49m
Data Points: 16 AIS positions
Period: 2026-10-23T08:05:46+00:00 to 2026-10-23T10:55:31+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 169.80000000000001136868377216160297393798828125,
    "points_in_zone": 16,
    "first_point": {
        "ts": "2026-10-23T08:05:46+00:00",
        "lat": 46.6921449999999964575181365944445133209228515625,
        "lon": 142.5762267000000065308995544910430908203125
    },
    "last_point": {
        "ts": "2026-10-23T10:55:31+00:00",
        "lat": 46.69258330000000256632119999267160892486572265625,
        "lon": 142.576019999999999754436430521309375762939453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 08:05 UTC 75.0% ▼

Duration: 4h 13m
Radius: 78 meters
Data Points: 31 AIS positions
Centroid: 46.6142, 142.5299
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 78,
    "duration_minutes": 253.400000000000005684341886080801486968994140625,
    "points": 31,
    "centroid": {
        "lat": 46.614184680645166736212559044361114501953125,
        "lon": 142.52988230645161138454568572342395782470703125
    },
    "bbox": {
        "min_lat": 46.6139366999999964491507853381335735321044921875,
        "min_lon": 142.52906500000000278305378742516040802001953125,
        "max_lat": 46.61460329999999885330908000469207763671875,
        "max_lon": 142.53019829999999501524143852293491363525390625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 08:05 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 13m
Data Points: 31 AIS positions
Period: 2026-10-23T08:05:42+00:00 to 2026-10-23T12:19:04+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 253.400000000000005684341886080801486968994140625,
    "points_in_zone": 31,
    "first_point": {
        "ts": "2026-10-23T08:05:42+00:00",
        "lat": 46.6142099999999999226929503493010997772216796875,
        "lon": 142.52974330000000691143213771283626556396484375
    },
    "last_point": {
        "ts": "2026-10-23T12:19:04+00:00",
        "lat": 46.61395999999999872898115427233278751373291015625,
        "lon": 142.530043299999988448689691722393035888671875
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 07:40 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 1h 11m
Data Points: 8 AIS positions
Period: 2026-10-23T07:40:37+00:00 to 2026-10-23T08:52:02+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 71.400000000000005684341886080801486968994140625,
    "points_in_zone": 8,
    "first_point": {
        "ts": "2026-10-23T07:40:37+00:00",
        "lat": 46.649266699999998309067450463771820068359375,
        "lon": 142.54298330000000305517460219562053680419921875
    },
    "last_point": {
        "ts": "2026-10-23T08:52:02+00:00",
        "lat": 46.649716699999999036663211882114410400390625,
        "lon": 142.542633300000005647234502248466014862060546875
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 07:40 UTC 82/100 ▼

Vessel A: IMO 9183817 (BUKHTA NAGAEVA) RUSSIA

Vessel B: SOLARIS (SOLARIS) OMAN

Minimum Distance: 68 meters
Average Distance: 155 meters
Duration: 1h 4m
Period: 2026-10-23T07:40:37+00:00 to 2026-10-23T08:44:54+00:00
Vessel A Avg Speed: 0.0 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 82/100

High-confidence STS candidate. Two tankers (BUKHTA NAGAEVA and SOLARIS) maintained close proximity (min 68m, avg 155m) for 64 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 68m, avg 155m
Duration	15/25	Duration 64 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	12/15	Distance variance ±39m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T13:30:04.136586+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273219140,
        "imo": 9183817,
        "name": "BUKHTA NAGAEVA",
        "flag": "RUSSIA"
    },
    "vessel_b": {
        "mmsi": 461000248,
        "imo": 9333436,
        "name": "SOLARIS",
        "flag": "OMAN"
    },
    "min_distance_m": 68.400000000000005684341886080801486968994140625,
    "avg_distance_m": 154.80000000000001136868377216160297393798828125,
    "distance_consistency_m": 39.2999999999999971578290569595992565155029296875,
    "duration_minutes": 64.2999999999999971578290569595992565155029296875,
    "overlap_duration_s": 3857,
    "speed_a_avg": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.070000000000000006661338147750939242541790008544921875,
    "speed_b_std": 0.08000000000000000166533453693773481063544750213623046875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.040000000000000000832667268468867405317723751068115234375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.070000000000000006661338147750939242541790008544921875,
            "max_sog": 0.200000000000000011102230246251565404236316680908203125
        }
    },
    "time_window": {
        "start": "2026-10-23T07:40:37+00:00",
        "end": "2026-10-23T08:44:54+00:00"
    },
    "points_count": {
        "vessel_a": 7,
        "vessel_b": 7
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 82,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 68m, avg 155m"
            },
            "duration": {
                "score": 15,
                "max": 25,
                "detail": "Duration 64 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 12,
                "max": 15,
                "detail": "Distance variance \u00b139m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (BUKHTA NAGAEVA and SOLARIS) maintained close proximity (min 68m, avg 155m) for 64 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.6499189999999970268618199042975902557373046875,
            "lon": 142.542867900000004510729922913014888763427734375
        },
        "time_window": {
            "start_ts": "2026-10-23T07:40:37+00:00",
            "end_ts": "2026-10-23T08:44:54+00:00"
        },
        "searched_at": "2026-10-23T13:30:04.136586+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 07:23 UTC 65/100 ▼

Vessel A: IMO 9084401 (AZOV) Russia

Vessel B: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Minimum Distance: 298 meters
Average Distance: 299 meters
Duration: 35 minutes
Period: 2026-10-23T07:23:21+00:00 to 2026-10-23T07:59:01+00:00
Vessel A Avg Speed: 0.2 knots
Vessel B Avg Speed: 0.3 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 65/100

Moderate-confidence STS candidate. Two tankers (AZOV and ZAPRAVSHCHIK 05) maintained close proximity (min 298m, avg 299m) for 36 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 298m, avg 299m
Duration	5/25	Duration 36 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T14:00:01.750013+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "min_distance_m": 297.69999999999998863131622783839702606201171875,
    "avg_distance_m": 298.80000000000001136868377216160297393798828125,
    "distance_consistency_m": 0.59999999999999997779553950749686919152736663818359375,
    "duration_minutes": 35.7000000000000028421709430404007434844970703125,
    "overlap_duration_s": 2140,
    "speed_a_avg": 0.1700000000000000122124532708767219446599483489990234375,
    "speed_a_std": 0.11999999999999999555910790149937383830547332763671875,
    "speed_b_avg": 0.25,
    "speed_b_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.1700000000000000122124532708767219446599483489990234375,
            "max_sog": 0.299999999999999988897769753748434595763683319091796875
        },
        "vessel_b": {
            "avg_sog": 0.25,
            "max_sog": 0.299999999999999988897769753748434595763683319091796875
        }
    },
    "time_window": {
        "start": "2026-10-23T07:23:21+00:00",
        "end": "2026-10-23T07:59:01+00:00"
    },
    "points_count": {
        "vessel_a": 8,
        "vessel_b": 8
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 65,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 298m, avg 299m"
            },
            "duration": {
                "score": 5,
                "max": 25,
                "detail": "Duration 36 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "Moderate-confidence STS candidate. Two tankers (AZOV and ZAPRAVSHCHIK 05) maintained close proximity (min 298m, avg 299m) for 36 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.62476079999999711844793637283146381378173828125,
            "lon": 142.7675490999999965424649417400360107421875
        },
        "time_window": {
            "start_ts": "2026-10-23T07:23:21+00:00",
            "end_ts": "2026-10-23T07:59:01+00:00"
        },
        "searched_at": "2026-10-23T14:00:01.750013+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 07:12 UTC 75/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Minimum Distance: 290 meters
Average Distance: 291 meters
Duration: 1h 24m
Period: 2026-10-23T07:12:50+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.1 knots
Vessel B Avg Speed: 0.3 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 75/100

Moderate-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 290m, avg 291m) for 84 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.3 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 290m, avg 291m
Duration	15/25	Duration 84 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T13:45:10.082126+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "min_distance_m": 289.80000000000001136868377216160297393798828125,
    "avg_distance_m": 291.30000000000001136868377216160297393798828125,
    "distance_consistency_m": 1,
    "duration_minutes": 84,
    "overlap_duration_s": 5040,
    "speed_a_avg": 0.08000000000000000166533453693773481063544750213623046875,
    "speed_a_std": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_b_avg": 0.2800000000000000266453525910037569701671600341796875,
    "speed_b_std": 0.13000000000000000444089209850062616169452667236328125,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.08000000000000000166533453693773481063544750213623046875,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.2800000000000000266453525910037569701671600341796875,
            "max_sog": 0.5
        }
    },
    "time_window": {
        "start": "2026-10-23T07:12:50+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 5,
        "vessel_b": 5
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 75,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 290m, avg 291m"
            },
            "duration": {
                "score": 15,
                "max": 25,
                "detail": "Duration 84 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "Moderate-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 290m, avg 291m) for 84 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.3 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.62481520000000045911292545497417449951171875,
            "lon": 142.7675418000000036045094020664691925048828125
        },
        "time_window": {
            "start_ts": "2026-10-23T07:12:50+00:00",
            "end_ts": "2026-10-23T08:36:50+00:00"
        },
        "searched_at": "2026-10-23T13:45:10.082126+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 07:12 UTC 75.0% ▼

Duration: 1h 30m
Radius: 1 meters
Data Points: 10 AIS positions
Centroid: 46.6256, 142.7660
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.100000000000000088817841970012523233890533447265625,
    "duration_minutes": 90,
    "points": 10,
    "centroid": {
        "lat": 46.6255521799999996801489032804965972900390625,
        "lon": 142.765970500000008769347914494574069976806640625
    },
    "bbox": {
        "min_lat": 46.6255450000000024601831682957708835601806640625,
        "min_lon": 142.765958299999994096651789732277393341064453125,
        "max_lat": 46.62555669999999707897586631588637828826904296875,
        "max_lon": 142.76597670000001016887836158275604248046875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 07:12 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 1h 30m
Data Points: 10 AIS positions
Period: 2026-10-23T07:12:46+00:00 to 2026-10-23T08:42:46+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 90,
    "points_in_zone": 10,
    "first_point": {
        "ts": "2026-10-23T07:12:46+00:00",
        "lat": 46.62554829999999839174051885493099689483642578125,
        "lon": 142.76596499999999423380359075963497161865234375
    },
    "last_point": {
        "ts": "2026-10-23T08:42:46+00:00",
        "lat": 46.62555669999999707897586631588637828826904296875,
        "lon": 142.765974999999997407940099947154521942138671875
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 07:06 UTC 90/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 11 meters
Average Distance: 12 meters
Duration: 1h 30m
Period: 2026-10-23T07:06:50+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.1 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 90/100

High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 11m, avg 12m) for 90 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 11m, avg 12m
Duration	20/25	Duration 90 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T13:45:03.905793+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 10.5999999999999996447286321199499070644378662109375,
    "avg_distance_m": 11.5999999999999996447286321199499070644378662109375,
    "distance_consistency_m": 0.90000000000000002220446049250313080847263336181640625,
    "duration_minutes": 90,
    "overlap_duration_s": 5400,
    "speed_a_avg": 0.070000000000000006661338147750939242541790008544921875,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.1700000000000000122124532708767219446599483489990234375,
    "speed_b_std": 0.11999999999999999555910790149937383830547332763671875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.070000000000000006661338147750939242541790008544921875,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.1700000000000000122124532708767219446599483489990234375,
            "max_sog": 0.40000000000000002220446049250313080847263336181640625
        }
    },
    "time_window": {
        "start": "2026-10-23T07:06:50+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 6,
        "vessel_b": 6
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 90,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 11m, avg 12m"
            },
            "duration": {
                "score": 20,
                "max": 25,
                "detail": "Duration 90 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 11m, avg 12m) for 90 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.624025799999998298517311923205852508544921875,
            "lon": 142.769122699999996939368429593741893768310546875
        },
        "time_window": {
            "start_ts": "2026-10-23T07:06:50+00:00",
            "end_ts": "2026-10-23T08:36:50+00:00"
        },
        "searched_at": "2026-10-23T13:45:03.905793+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 07:06 UTC 75.0% ▼

Duration: 6h 21m
Radius: 4 meters
Data Points: 12 AIS positions
Centroid: 46.6197, 142.8995
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 3.899999999999999911182158029987476766109466552734375,
    "duration_minutes": 381,
    "points": 12,
    "centroid": {
        "lat": 46.619742500000000973159330897033214569091796875,
        "lon": 142.899478749999985893737175501883029937744140625
    },
    "bbox": {
        "min_lat": 46.61971330000000079962774179875850677490234375,
        "min_lon": 142.8994500000000016370904631912708282470703125,
        "max_lat": 46.6197700000000025966073735617101192474365234375,
        "max_lon": 142.899501700000001847001840360462665557861328125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 07:06 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 26m
Data Points: 9 AIS positions
Period: 2026-10-23T07:51:13+00:00 to 2026-10-23T14:18:10+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 386.8999999999999772626324556767940521240234375,
    "points_in_zone": 9,
    "first_point": {
        "ts": "2026-10-23T07:51:13+00:00",
        "lat": 46.6197317000000026609995984472334384918212890625,
        "lon": 142.899481699999995498728821985423564910888671875
    },
    "last_point": {
        "ts": "2026-10-23T14:18:10+00:00",
        "lat": 46.61975000000000335376171278767287731170654296875,
        "lon": 142.89951500000000805812305770814418792724609375
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 07:05 UTC 75.0% ▼

Duration: 5h 13m
Radius: 85 meters
Data Points: 39 AIS positions
Centroid: 46.6141, 142.5299
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 84.5,
    "duration_minutes": 313.3999999999999772626324556767940521240234375,
    "points": 39,
    "centroid": {
        "lat": 46.6141270538461611749880830757319927215576171875,
        "lon": 142.529925423076889501317054964601993560791015625
    },
    "bbox": {
        "min_lat": 46.6137599999999991950971889309585094451904296875,
        "min_lon": 142.52906500000000278305378742516040802001953125,
        "max_lat": 46.61460329999999885330908000469207763671875,
        "max_lon": 142.53019829999999501524143852293491363525390625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 07:05 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 5h 13m
Data Points: 39 AIS positions
Period: 2026-10-23T07:05:41+00:00 to 2026-10-23T12:19:04+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 313.3999999999999772626324556767940521240234375,
    "points_in_zone": 39,
    "first_point": {
        "ts": "2026-10-23T07:05:41+00:00",
        "lat": 46.61395830000000017889760783873498439788818359375,
        "lon": 142.530088299999988521449267864227294921875
    },
    "last_point": {
        "ts": "2026-10-23T12:19:04+00:00",
        "lat": 46.61395999999999872898115427233278751373291015625,
        "lon": 142.530043299999988448689691722393035888671875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 07:04 UTC 75.0% ▼

Duration: 6h 27m
Radius: 58 meters
Data Points: 43 AIS positions
Centroid: 46.5364, 142.9391
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 57.89999999999999857891452847979962825775146484375,
    "duration_minutes": 387,
    "points": 43,
    "centroid": {
        "lat": 46.5363682186046645483656902797520160675048828125,
        "lon": 142.9390923697674224968068301677703857421875
    },
    "bbox": {
        "min_lat": 46.53606500000000067984728957526385784149169921875,
        "min_lon": 142.938573300000001609078026376664638519287109375,
        "max_lat": 46.53659669999999692890924052335321903228759765625,
        "max_lon": 142.9397066999999879044480621814727783203125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 07:04 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 27m
Data Points: 43 AIS positions
Period: 2026-10-23T07:55:51+00:00 to 2026-10-23T14:22:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 387,
    "points_in_zone": 43,
    "first_point": {
        "ts": "2026-10-23T07:55:51+00:00",
        "lat": 46.53622500000000172803993336856365203857421875,
        "lon": 142.939391699999987395131029188632965087890625
    },
    "last_point": {
        "ts": "2026-10-23T14:22:50+00:00",
        "lat": 46.53640169999999898209352977573871612548828125,
        "lon": 142.939024999999986675902619026601314544677734375
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 07:02 UTC 75.0% ▼

Duration: 3h 52m
Radius: 69 meters
Data Points: 23 AIS positions
Centroid: 46.6922, 142.5762
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 68.900000000000005684341886080801486968994140625,
    "duration_minutes": 232.80000000000001136868377216160297393798828125,
    "points": 23,
    "centroid": {
        "lat": 46.69220042608696275010515819303691387176513671875,
        "lon": 142.57616739130435234983451664447784423828125
    },
    "bbox": {
        "min_lat": 46.69163999999999958845364744774997234344482421875,
        "min_lon": 142.57553999999998950443114154040813446044921875,
        "max_lat": 46.6926150000000035333869163878262042999267578125,
        "max_lon": 142.576448300000009794530342333018779754638671875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 07:02 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 3h 52m
Data Points: 23 AIS positions
Period: 2026-10-23T07:02:46+00:00 to 2026-10-23T10:55:31+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 232.80000000000001136868377216160297393798828125,
    "points_in_zone": 23,
    "first_point": {
        "ts": "2026-10-23T07:02:46+00:00",
        "lat": 46.691973300000000790532794781029224395751953125,
        "lon": 142.576401699999991024014889262616634368896484375
    },
    "last_point": {
        "ts": "2026-10-23T10:55:31+00:00",
        "lat": 46.69258330000000256632119999267160892486572265625,
        "lon": 142.576019999999999754436430521309375762939453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 07:02 UTC 75.0% ▼

Duration: 1h 46m
Radius: 1 meters
Data Points: 23 AIS positions
Centroid: 46.6240, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.1999999999999999555910790149937383830547332763671875,
    "duration_minutes": 106.5,
    "points": 23,
    "centroid": {
        "lat": 46.62397413478259977637208066880702972412109375,
        "lon": 142.769126521739138979683048091828823089599609375
    },
    "bbox": {
        "min_lat": 46.6239632999999997764462023042142391204833984375,
        "min_lon": 142.76911169999999628998921252787113189697265625,
        "max_lat": 46.62398329999999901929186307825148105621337890625,
        "max_lon": 142.7691383000000087122316472232341766357421875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 07:02 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 1h 46m
Data Points: 23 AIS positions
Period: 2026-10-23T07:02:31+00:00 to 2026-10-23T08:49:03+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 106.5,
    "points_in_zone": 23,
    "first_point": {
        "ts": "2026-10-23T07:02:31+00:00",
        "lat": 46.623971699999998463681549765169620513916015625,
        "lon": 142.769129999999989877323969267308712005615234375
    },
    "last_point": {
        "ts": "2026-10-23T08:49:03+00:00",
        "lat": 46.6239632999999997764462023042142391204833984375,
        "lon": 142.769126699999986840339261107146739959716796875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 07:01 UTC 75.0% ▼

Duration: 1h 44m
Radius: 383 meters
Data Points: 13 AIS positions
Centroid: 46.6502, 142.5431
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 382.80000000000001136868377216160297393798828125,
    "duration_minutes": 104.5,
    "points": 13,
    "centroid": {
        "lat": 46.6502333307692396147103863768279552459716796875,
        "lon": 142.543108969230758020785287953913211822509765625
    },
    "bbox": {
        "min_lat": 46.6467999999999989313437254168093204498291015625,
        "min_lon": 142.5409832999999935054802335798740386962890625,
        "max_lat": 46.65093329999999838264557183720171451568603515625,
        "max_lon": 142.543800000000004501998773775994777679443359375
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 07:01 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 1h 44m
Data Points: 13 AIS positions
Period: 2026-10-23T07:01:37+00:00 to 2026-10-23T08:46:08+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 104.5,
    "points_in_zone": 13,
    "first_point": {
        "ts": "2026-10-23T07:01:37+00:00",
        "lat": 46.6467999999999989313437254168093204498291015625,
        "lon": 142.543499999999994543031789362430572509765625
    },
    "last_point": {
        "ts": "2026-10-23T08:46:08+00:00",
        "lat": 46.65008329999999858728187973611056804656982421875,
        "lon": 142.5409832999999935054802335798740386962890625
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach GALAXY (IMO: 9826902, MMSI: 461000329)

Oct 23, 2026 07:01 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 32m
Data Points: 16 AIS positions
Period: 2026-10-23T07:51:12+00:00 to 2026-10-23T14:23:11+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 392,
    "points_in_zone": 16,
    "first_point": {
        "ts": "2026-10-23T07:51:12+00:00",
        "lat": 46.296920000000000072759576141834259033203125,
        "lon": 142.810958300000010012809070758521556854248046875
    },
    "last_point": {
        "ts": "2026-10-23T14:23:11+00:00",
        "lat": 46.2574283000000008314600563608109951019287109375,
        "lon": 142.760553299999997989289113320410251617431640625
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 07:00 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 1h 36m
Data Points: 7 AIS positions
Period: 2026-10-23T07:00:49+00:00 to 2026-10-23T08:36:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 96,
    "points_in_zone": 7,
    "first_point": {
        "ts": "2026-10-23T07:00:49+00:00",
        "lat": 46.62408330000000233894752454943954944610595703125,
        "lon": 142.7691317000000026382622309029102325439453125
    },
    "last_point": {
        "ts": "2026-10-23T08:36:50+00:00",
        "lat": 46.62408330000000233894752454943954944610595703125,
        "lon": 142.7691317000000026382622309029102325439453125
    }
}

Methodology: 2026.01.18

Sts Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 06:39 UTC 95/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 11 meters
Average Distance: 12 meters
Duration: 2h 36m
Period: 2026-10-23T06:00:49+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.1 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 95/100

High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 11m, avg 12m) for 156 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 11m, avg 12m
Duration	25/25	Duration 156 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 10.5999999999999996447286321199499070644378662109375,
    "avg_distance_m": 11.699999999999999289457264239899814128875732421875,
    "distance_consistency_m": 1.100000000000000088817841970012523233890533447265625,
    "duration_minutes": 156,
    "overlap_duration_s": 9361,
    "speed_a_avg": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.1499999999999999944488848768742172978818416595458984375,
    "speed_b_std": 0.11999999999999999555910790149937383830547332763671875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.05000000000000000277555756156289135105907917022705078125,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.1499999999999999944488848768742172978818416595458984375,
            "max_sog": 0.40000000000000002220446049250313080847263336181640625
        }
    },
    "time_window": {
        "start": "2026-10-23T06:00:49+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 13,
        "vessel_b": 13
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 95,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 11m, avg 12m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 156 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 11m, avg 12m) for 156 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 06:34 UTC 75.0% ▼

Duration: 2h 17m
Radius: 55 meters
Data Points: 10 AIS positions
Centroid: 46.6493, 142.5429
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 55,
    "duration_minutes": 137.5,
    "points": 10,
    "centroid": {
        "lat": 46.6493416800000062494291341863572597503662109375,
        "lon": 142.54289833000001408436219207942485809326171875
    },
    "bbox": {
        "min_lat": 46.6488666999999992412995197810232639312744140625,
        "min_lon": 142.542633300000005647234502248466014862060546875,
        "max_lat": 46.649716699999999036663211882114410400390625,
        "max_lon": 142.543100000000009686118573881685733795166015625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 06:34 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 17m
Data Points: 10 AIS positions
Period: 2026-10-23T06:34:34+00:00 to 2026-10-23T08:52:02+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 137.5,
    "points_in_zone": 10,
    "first_point": {
        "ts": "2026-10-23T06:34:34+00:00",
        "lat": 46.6488666999999992412995197810232639312744140625,
        "lon": 142.543100000000009686118573881685733795166015625
    },
    "last_point": {
        "ts": "2026-10-23T08:52:02+00:00",
        "lat": 46.649716699999999036663211882114410400390625,
        "lon": 142.542633300000005647234502248466014862060546875
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 06:34 UTC 88/100 ▼

Vessel A: IMO 9183817 (BUKHTA NAGAEVA) RUSSIA

Vessel B: SOLARIS (SOLARIS) OMAN

Minimum Distance: 43 meters
Average Distance: 141 meters
Duration: 2h 10m
Period: 2026-10-23T06:34:34+00:00 to 2026-10-23T08:44:54+00:00
Vessel A Avg Speed: 0.0 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 88/100

High-confidence STS candidate. Two tankers (BUKHTA NAGAEVA and SOLARIS) maintained close proximity (min 43m, avg 141m) for 130 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.1 knots). Moderate distance variation observed during the encounter. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 43m, avg 141m
Duration	25/25	Duration 130 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	8/15	Distance variance ±50m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T12:45:10.712340+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273219140,
        "imo": 9183817,
        "name": "BUKHTA NAGAEVA",
        "flag": "RUSSIA"
    },
    "vessel_b": {
        "mmsi": 461000248,
        "imo": 9333436,
        "name": "SOLARIS",
        "flag": "OMAN"
    },
    "min_distance_m": 42.89999999999999857891452847979962825775146484375,
    "avg_distance_m": 140.69999999999998863131622783839702606201171875,
    "distance_consistency_m": 50.2000000000000028421709430404007434844970703125,
    "duration_minutes": 130.30000000000001136868377216160297393798828125,
    "overlap_duration_s": 7820,
    "speed_a_avg": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.08000000000000000166533453693773481063544750213623046875,
    "speed_b_std": 0.070000000000000006661338147750939242541790008544921875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.040000000000000000832667268468867405317723751068115234375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.08000000000000000166533453693773481063544750213623046875,
            "max_sog": 0.200000000000000011102230246251565404236316680908203125
        }
    },
    "time_window": {
        "start": "2026-10-23T06:34:34+00:00",
        "end": "2026-10-23T08:44:54+00:00"
    },
    "points_count": {
        "vessel_a": 9,
        "vessel_b": 9
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 88,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 43m, avg 141m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 130 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 8,
                "max": 15,
                "detail": "Distance variance \u00b150m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (BUKHTA NAGAEVA and SOLARIS) maintained close proximity (min 43m, avg 141m) for 130 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.1 knots). Moderate distance variation observed during the encounter. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.6496518000000008896677172742784023284912109375,
            "lon": 142.542968500000000631189323030412197113037109375
        },
        "time_window": {
            "start_ts": "2026-10-23T06:34:34+00:00",
            "end_ts": "2026-10-23T08:44:54+00:00"
        },
        "searched_at": "2026-10-23T12:45:10.712340+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 06:32 UTC 75.0% ▼

Duration: 4h 22m
Radius: 67 meters
Data Points: 27 AIS positions
Centroid: 46.6922, 142.5762
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 67.099999999999994315658113919198513031005859375,
    "duration_minutes": 262.80000000000001136868377216160297393798828125,
    "points": 27,
    "centroid": {
        "lat": 46.6921704296296269376398413442075252532958984375,
        "lon": 142.5762014814814619967364706099033355712890625
    },
    "bbox": {
        "min_lat": 46.69163999999999958845364744774997234344482421875,
        "min_lon": 142.57553999999998950443114154040813446044921875,
        "max_lat": 46.6926150000000035333869163878262042999267578125,
        "max_lon": 142.576448300000009794530342333018779754638671875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 06:32 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 22m
Data Points: 27 AIS positions
Period: 2026-10-23T06:32:46+00:00 to 2026-10-23T10:55:31+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 262.80000000000001136868377216160297393798828125,
    "points_in_zone": 27,
    "first_point": {
        "ts": "2026-10-23T06:32:46+00:00",
        "lat": 46.69196670000000182199073606170713901519775390625,
        "lon": 142.57639499999999088686308823525905609130859375
    },
    "last_point": {
        "ts": "2026-10-23T10:55:31+00:00",
        "lat": 46.69258330000000256632119999267160892486572265625,
        "lon": 142.576019999999999754436430521309375762939453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 06:21 UTC 75.0% ▼

Duration: 6h 30m
Radius: 5 meters
Data Points: 14 AIS positions
Centroid: 46.6197, 142.8995
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 5,
    "duration_minutes": 390,
    "points": 14,
    "centroid": {
        "lat": 46.61974845714285464737258735112845897674560546875,
        "lon": 142.89947821428569341151160188019275665283203125
    },
    "bbox": {
        "min_lat": 46.61971330000000079962774179875850677490234375,
        "min_lon": 142.8994500000000016370904631912708282470703125,
        "max_lat": 46.619793299999997771010384894907474517822265625,
        "max_lon": 142.899489999999985911927069537341594696044921875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 06:21 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 30m
Data Points: 14 AIS positions
Period: 2026-10-23T06:21:09+00:00 to 2026-10-23T12:51:11+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 390,
    "points_in_zone": 14,
    "first_point": {
        "ts": "2026-10-23T06:21:09+00:00",
        "lat": 46.619793299999997771010384894907474517822265625,
        "lon": 142.899480000000011159499990753829479217529296875
    },
    "last_point": {
        "ts": "2026-10-23T12:51:11+00:00",
        "lat": 46.6197700000000025966073735617101192474365234375,
        "lon": 142.899484999999998535713530145585536956787109375
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 06:13 UTC 75.0% ▼

Duration: 6h 36m
Radius: 53 meters
Data Points: 38 AIS positions
Centroid: 46.5363, 142.9391
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 52.60000000000000142108547152020037174224853515625,
    "duration_minutes": 396,
    "points": 38,
    "centroid": {
        "lat": 46.53632745789474256525863893330097198486328125,
        "lon": 142.939136313157860058709047734737396240234375
    },
    "bbox": {
        "min_lat": 46.53606500000000067984728957526385784149169921875,
        "min_lon": 142.938573300000001609078026376664638519287109375,
        "max_lat": 46.53659669999999692890924052335321903228759765625,
        "max_lon": 142.9397066999999879044480621814727783203125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 06:13 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 36m
Data Points: 38 AIS positions
Period: 2026-10-23T06:13:51+00:00 to 2026-10-23T12:49:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 396,
    "points_in_zone": 38,
    "first_point": {
        "ts": "2026-10-23T06:13:51+00:00",
        "lat": 46.53617669999999861829564906656742095947265625,
        "lon": 142.939286699999996699261828325688838958740234375
    },
    "last_point": {
        "ts": "2026-10-23T12:49:50+00:00",
        "lat": 46.53647829999999885330908000469207763671875,
        "lon": 142.93892329999999901701812632381916046142578125
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 06:07 UTC 85/100 ▼

Vessel A: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 298 meters
Average Distance: 299 meters
Duration: 2h 35m
Period: 2026-10-23T06:07:46+00:00 to 2026-10-23T08:42:46+00:00
Vessel A Avg Speed: 0.2 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 85/100

High-confidence STS candidate. Two tankers (ZAPRAVSHCHIK 05 and AZOV) maintained close proximity (min 298m, avg 299m) for 155 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 298m, avg 299m
Duration	25/25	Duration 155 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T13:00:01.672813+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 297.69999999999998863131622783839702606201171875,
    "avg_distance_m": 299,
    "distance_consistency_m": 0.8000000000000000444089209850062616169452667236328125,
    "duration_minutes": 155,
    "overlap_duration_s": 9300,
    "speed_a_avg": 0.2300000000000000099920072216264088638126850128173828125,
    "speed_a_std": 0.14000000000000001332267629550187848508358001708984375,
    "speed_b_avg": 0.11000000000000000055511151231257827021181583404541015625,
    "speed_b_std": 0.11999999999999999555910790149937383830547332763671875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.2300000000000000099920072216264088638126850128173828125,
            "max_sog": 0.5
        },
        "vessel_b": {
            "avg_sog": 0.11000000000000000055511151231257827021181583404541015625,
            "max_sog": 0.299999999999999988897769753748434595763683319091796875
        }
    },
    "time_window": {
        "start": "2026-10-23T06:07:46+00:00",
        "end": "2026-10-23T08:42:46+00:00"
    },
    "points_count": {
        "vessel_a": 18,
        "vessel_b": 18
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 85,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 298m, avg 299m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 155 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (ZAPRAVSHCHIK 05 and AZOV) maintained close proximity (min 298m, avg 299m) for 155 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.62476310000000268018993665464222431182861328125,
            "lon": 142.76754879999998593120835721492767333984375
        },
        "time_window": {
            "start_ts": "2026-10-23T06:07:46+00:00",
            "end_ts": "2026-10-23T08:42:46+00:00"
        },
        "searched_at": "2026-10-23T13:00:01.672813+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 06:05 UTC 75.0% ▼

Duration: 2h 40m
Radius: 361 meters
Data Points: 20 AIS positions
Centroid: 46.6500, 142.5426
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 361.19999999999998863131622783839702606201171875,
    "duration_minutes": 160.30000000000001136868377216160297393798828125,
    "points": 20,
    "centroid": {
        "lat": 46.6499916650000017170896171592175960540771484375,
        "lon": 142.54261249999996152837411500513553619384765625
    },
    "bbox": {
        "min_lat": 46.6467999999999989313437254168093204498291015625,
        "min_lon": 142.5405332999999927778844721615314483642578125,
        "max_lat": 46.65093329999999838264557183720171451568603515625,
        "max_lon": 142.5443500000000085492501966655254364013671875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 06:05 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 40m
Data Points: 20 AIS positions
Period: 2026-10-23T06:05:51+00:00 to 2026-10-23T08:46:08+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 160.30000000000001136868377216160297393798828125,
    "points_in_zone": 20,
    "first_point": {
        "ts": "2026-10-23T06:05:51+00:00",
        "lat": 46.6502167000000014240868040360510349273681640625,
        "lon": 142.5405332999999927778844721615314483642578125
    },
    "last_point": {
        "ts": "2026-10-23T08:46:08+00:00",
        "lat": 46.65008329999999858728187973611056804656982421875,
        "lon": 142.5409832999999935054802335798740386962890625
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach GALAXY (IMO: 9826902, MMSI: 461000329)

Oct 23, 2026 06:04 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 28m
Data Points: 25 AIS positions
Period: 2026-10-23T06:44:22+00:00 to 2026-10-23T13:12:30+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 388.1000000000000227373675443232059478759765625,
    "points_in_zone": 25,
    "first_point": {
        "ts": "2026-10-23T06:44:22+00:00",
        "lat": 46.37086500000000199861460714600980281829833984375,
        "lon": 142.86173170000000709478626959025859832763671875
    },
    "last_point": {
        "ts": "2026-10-23T13:12:30+00:00",
        "lat": 46.223264999999997826307662762701511383056640625,
        "lon": 142.733685000000008358256309293210506439208984375
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 06:03 UTC 75.0% ▼

Duration: 2h 45m
Radius: 2 meters
Data Points: 39 AIS positions
Centroid: 46.6240, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.5,
    "duration_minutes": 165.900000000000005684341886080801486968994140625,
    "points": 39,
    "centroid": {
        "lat": 46.62397470769230523046644520945847034454345703125,
        "lon": 142.76912931794873884427943266928195953369140625
    },
    "bbox": {
        "min_lat": 46.6239632999999997764462023042142391204833984375,
        "min_lon": 142.76911169999999628998921252787113189697265625,
        "max_lat": 46.62398830000000060636011767201125621795654296875,
        "max_lon": 142.769141700000005812398740090429782867431640625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 06:03 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 45m
Data Points: 39 AIS positions
Period: 2026-10-23T06:03:10+00:00 to 2026-10-23T08:49:03+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 165.900000000000005684341886080801486968994140625,
    "points_in_zone": 39,
    "first_point": {
        "ts": "2026-10-23T06:03:10+00:00",
        "lat": 46.62398830000000060636011767201125621795654296875,
        "lon": 142.769126699999986840339261107146739959716796875
    },
    "last_point": {
        "ts": "2026-10-23T08:49:03+00:00",
        "lat": 46.6239632999999997764462023042142391204833984375,
        "lon": 142.769126699999986840339261107146739959716796875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 06:02 UTC 75.0% ▼

Duration: 6h 16m
Radius: 91 meters
Data Points: 46 AIS positions
Centroid: 46.6141, 142.5300
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 90.599999999999994315658113919198513031005859375,
    "duration_minutes": 376.3999999999999772626324556767940521240234375,
    "points": 46,
    "centroid": {
        "lat": 46.6140761608695726181395002640783786773681640625,
        "lon": 142.529966556521713982874643988907337188720703125
    },
    "bbox": {
        "min_lat": 46.61370329999999739811755716800689697265625,
        "min_lon": 142.52906500000000278305378742516040802001953125,
        "max_lat": 46.61460329999999885330908000469207763671875,
        "max_lon": 142.5302566999999953623046167194843292236328125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 06:02 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 16m
Data Points: 46 AIS positions
Period: 2026-10-23T06:02:41+00:00 to 2026-10-23T12:19:04+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 376.3999999999999772626324556767940521240234375,
    "points_in_zone": 46,
    "first_point": {
        "ts": "2026-10-23T06:02:41+00:00",
        "lat": 46.613758300000000645013642497360706329345703125,
        "lon": 142.53019000000000460204319097101688385009765625
    },
    "last_point": {
        "ts": "2026-10-23T12:19:04+00:00",
        "lat": 46.61395999999999872898115427233278751373291015625,
        "lon": 142.530043299999988448689691722393035888671875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 06:01 UTC 75.0% ▼

Duration: 2h 41m
Radius: 1 meters
Data Points: 19 AIS positions
Centroid: 46.6256, 142.7660
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.100000000000000088817841970012523233890533447265625,
    "duration_minutes": 161,
    "points": 19,
    "centroid": {
        "lat": 46.62555228947366003922070376574993133544921875,
        "lon": 142.765967805263159107198589481413364410400390625
    },
    "bbox": {
        "min_lat": 46.6255450000000024601831682957708835601806640625,
        "min_lon": 142.765958299999994096651789732277393341064453125,
        "max_lat": 46.62556169999999866604412090964615345001220703125,
        "max_lon": 142.76597670000001016887836158275604248046875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 06:01 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 41m
Data Points: 19 AIS positions
Period: 2026-10-23T06:01:47+00:00 to 2026-10-23T08:42:46+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 161,
    "points_in_zone": 19,
    "first_point": {
        "ts": "2026-10-23T06:01:47+00:00",
        "lat": 46.62556169999999866604412090964615345001220703125,
        "lon": 142.76596499999999423380359075963497161865234375
    },
    "last_point": {
        "ts": "2026-10-23T08:42:46+00:00",
        "lat": 46.62555669999999707897586631588637828826904296875,
        "lon": 142.765974999999997407940099947154521942138671875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 06:00 UTC 75.0% ▼

Duration: 2h 36m
Radius: 4 meters
Data Points: 13 AIS positions
Centroid: 46.6241, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 4.0999999999999996447286321199499070644378662109375,
    "duration_minutes": 156,
    "points": 13,
    "centroid": {
        "lat": 46.62407948461540030393734923563897609710693359375,
        "lon": 142.7691175923076798426336608827114105224609375
    },
    "bbox": {
        "min_lat": 46.6240667000000001962689566425979137420654296875,
        "min_lon": 142.769100000000008776623872108757495880126953125,
        "max_lat": 46.62411670000000185609678737819194793701171875,
        "max_lon": 142.7691317000000026382622309029102325439453125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 06:00 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 36m
Data Points: 13 AIS positions
Period: 2026-10-23T06:00:49+00:00 to 2026-10-23T08:36:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 156,
    "points_in_zone": 13,
    "first_point": {
        "ts": "2026-10-23T06:00:49+00:00",
        "lat": 46.62411670000000185609678737819194793701171875,
        "lon": 142.769116700000012087912182323634624481201171875
    },
    "last_point": {
        "ts": "2026-10-23T08:36:50+00:00",
        "lat": 46.62408330000000233894752454943954944610595703125,
        "lon": 142.7691317000000026382622309029102325439453125
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 06:00 UTC 85/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Minimum Distance: 290 meters
Average Distance: 292 meters
Duration: 2h 36m
Period: 2026-10-23T06:00:49+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.1 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 85/100

High-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 290m, avg 292m) for 156 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 290m, avg 292m
Duration	25/25	Duration 156 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T12:45:05.925629+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "min_distance_m": 289.80000000000001136868377216160297393798828125,
    "avg_distance_m": 291.6000000000000227373675443232059478759765625,
    "distance_consistency_m": 1,
    "duration_minutes": 156,
    "overlap_duration_s": 9361,
    "speed_a_avg": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.190000000000000002220446049250313080847263336181640625,
    "speed_b_std": 0.13000000000000000444089209850062616169452667236328125,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.05000000000000000277555756156289135105907917022705078125,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.190000000000000002220446049250313080847263336181640625,
            "max_sog": 0.5
        }
    },
    "time_window": {
        "start": "2026-10-23T06:00:49+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 13,
        "vessel_b": 13
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 85,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 290m, avg 292m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 156 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 290m, avg 292m) for 156 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.6248156999999991967342793941497802734375,
            "lon": 142.767542099999985794056556187570095062255859375
        },
        "time_window": {
            "start_ts": "2026-10-23T06:00:49+00:00",
            "end_ts": "2026-10-23T08:36:50+00:00"
        },
        "searched_at": "2026-10-23T12:45:05.925629+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 05:55 UTC 75.0% ▼

Duration: 2h 56m
Radius: 51 meters
Data Points: 11 AIS positions
Centroid: 46.6493, 142.5429
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 51.2999999999999971578290569595992565155029296875,
    "duration_minutes": 176.69999999999998863131622783839702606201171875,
    "points": 11,
    "centroid": {
        "lat": 46.64929850000000755017026676796376705169677734375,
        "lon": 142.542918181818180300979292951524257659912109375
    },
    "bbox": {
        "min_lat": 46.6488666999999992412995197810232639312744140625,
        "min_lon": 142.542633300000005647234502248466014862060546875,
        "max_lat": 46.649716699999999036663211882114410400390625,
        "max_lon": 142.543116700000012997406884096562862396240234375
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 05:55 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 2h 56m
Data Points: 11 AIS positions
Period: 2026-10-23T05:55:19+00:00 to 2026-10-23T08:52:02+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 176.69999999999998863131622783839702606201171875,
    "points_in_zone": 11,
    "first_point": {
        "ts": "2026-10-23T05:55:19+00:00",
        "lat": 46.6488666999999992412995197810232639312744140625,
        "lon": 142.543116700000012997406884096562862396240234375
    },
    "last_point": {
        "ts": "2026-10-23T08:52:02+00:00",
        "lat": 46.649716699999999036663211882114410400390625,
        "lon": 142.542633300000005647234502248466014862060546875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 05:32 UTC 75.0% ▼

Duration: 5h 22m
Radius: 66 meters
Data Points: 29 AIS positions
Centroid: 46.6921, 142.5762
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 65.599999999999994315658113919198513031005859375,
    "duration_minutes": 322.80000000000001136868377216160297393798828125,
    "points": 29,
    "centroid": {
        "lat": 46.69214890689654140487618860788643360137939453125,
        "lon": 142.576217124137912151127238757908344268798828125
    },
    "bbox": {
        "min_lat": 46.69163999999999958845364744774997234344482421875,
        "min_lon": 142.57553999999998950443114154040813446044921875,
        "max_lat": 46.6926150000000035333869163878262042999267578125,
        "max_lon": 142.5765083000000004176399670541286468505859375
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 05:32 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 5h 22m
Data Points: 29 AIS positions
Period: 2026-10-23T05:32:45+00:00 to 2026-10-23T10:55:31+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 322.80000000000001136868377216160297393798828125,
    "points_in_zone": 29,
    "first_point": {
        "ts": "2026-10-23T05:32:45+00:00",
        "lat": 46.6920199999999994133759173564612865447998046875,
        "lon": 142.57634830000000647487468086183071136474609375
    },
    "last_point": {
        "ts": "2026-10-23T10:55:31+00:00",
        "lat": 46.69258330000000256632119999267160892486572265625,
        "lon": 142.576019999999999754436430521309375762939453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 05:16 UTC 75.0% ▼

Duration: 3h 29m
Radius: 374 meters
Data Points: 23 AIS positions
Centroid: 46.6501, 142.5426
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 373.8999999999999772626324556767940521240234375,
    "duration_minutes": 209.5,
    "points": 23,
    "centroid": {
        "lat": 46.65011159130434492681160918436944484710693359375,
        "lon": 142.5426485521738868555985391139984130859375
    },
    "bbox": {
        "min_lat": 46.6467999999999989313437254168093204498291015625,
        "min_lon": 142.540249999999986130205797962844371795654296875,
        "max_lat": 46.6522666999999984227542881853878498077392578125,
        "max_lon": 142.544516700000002629167283885180950164794921875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 05:16 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 3h 29m
Data Points: 23 AIS positions
Period: 2026-10-23T05:16:36+00:00 to 2026-10-23T08:46:08+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 209.5,
    "points_in_zone": 23,
    "first_point": {
        "ts": "2026-10-23T05:16:36+00:00",
        "lat": 46.6516333000000003039531293325126171112060546875,
        "lon": 142.5439000000000078216544352471828460693359375
    },
    "last_point": {
        "ts": "2026-10-23T08:46:08+00:00",
        "lat": 46.65008329999999858728187973611056804656982421875,
        "lon": 142.5409832999999935054802335798740386962890625
    }
}

Methodology: 2026.01.18

Sts Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 05:14 UTC 85/100 ▼

Vessel A: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 298 meters
Average Distance: 299 meters
Duration: 3h 27m
Period: 2026-10-23T05:15:47+00:00 to 2026-10-23T08:42:46+00:00
Vessel A Avg Speed: 0.2 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 85/100

High-confidence STS candidate. Two tankers (ZAPRAVSHCHIK 05 and AZOV) maintained close proximity (min 298m, avg 299m) for 207 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 298m, avg 299m
Duration	25/25	Duration 207 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 297.69999999999998863131622783839702606201171875,
    "avg_distance_m": 298.8999999999999772626324556767940521240234375,
    "distance_consistency_m": 0.6999999999999999555910790149937383830547332763671875,
    "duration_minutes": 207,
    "overlap_duration_s": 12419,
    "speed_a_avg": 0.179999999999999993338661852249060757458209991455078125,
    "speed_a_std": 0.14000000000000001332267629550187848508358001708984375,
    "speed_b_avg": 0.1000000000000000055511151231257827021181583404541015625,
    "speed_b_std": 0.11000000000000000055511151231257827021181583404541015625,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.179999999999999993338661852249060757458209991455078125,
            "max_sog": 0.5
        },
        "vessel_b": {
            "avg_sog": 0.1000000000000000055511151231257827021181583404541015625,
            "max_sog": 0.299999999999999988897769753748434595763683319091796875
        }
    },
    "time_window": {
        "start": "2026-10-23T05:15:47+00:00",
        "end": "2026-10-23T08:42:46+00:00"
    },
    "points_count": {
        "vessel_a": 29,
        "vessel_b": 29
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 85,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 298m, avg 299m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 207 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (ZAPRAVSHCHIK 05 and AZOV) maintained close proximity (min 298m, avg 299m) for 207 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 05:12 UTC 75.0% ▼

Duration: 3h 30m
Radius: 1 meters
Data Points: 30 AIS positions
Centroid: 46.6256, 142.7660
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.1999999999999999555910790149937383830547332763671875,
    "duration_minutes": 210,
    "points": 30,
    "centroid": {
        "lat": 46.62555406000001312349922955036163330078125,
        "lon": 142.765967220000021598025341518223285675048828125
    },
    "bbox": {
        "min_lat": 46.6255450000000024601831682957708835601806640625,
        "min_lon": 142.765958299999994096651789732277393341064453125,
        "max_lat": 46.62556500000000170302882906980812549591064453125,
        "max_lon": 142.76597670000001016887836158275604248046875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 05:12 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 3h 30m
Data Points: 30 AIS positions
Period: 2026-10-23T05:12:45+00:00 to 2026-10-23T08:42:46+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 210,
    "points_in_zone": 30,
    "first_point": {
        "ts": "2026-10-23T05:12:45+00:00",
        "lat": 46.62555329999999997880877344869077205657958984375,
        "lon": 142.765970000000010031726560555398464202880859375
    },
    "last_point": {
        "ts": "2026-10-23T08:42:46+00:00",
        "lat": 46.62555669999999707897586631588637828826904296875,
        "lon": 142.765974999999997407940099947154521942138671875
    }
}

Methodology: 2026.01.18

Sts Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 05:12 UTC 85/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Minimum Distance: 289 meters
Average Distance: 292 meters
Duration: 3h 24m
Period: 2026-10-23T05:12:49+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.0 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 85/100

High-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 289m, avg 292m) for 204 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 289m, avg 292m
Duration	25/25	Duration 204 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "min_distance_m": 288.8999999999999772626324556767940521240234375,
    "avg_distance_m": 291.5,
    "distance_consistency_m": 1.100000000000000088817841970012523233890533447265625,
    "duration_minutes": 204,
    "overlap_duration_s": 12241,
    "speed_a_avg": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.1700000000000000122124532708767219446599483489990234375,
    "speed_b_std": 0.11999999999999999555910790149937383830547332763671875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.040000000000000000832667268468867405317723751068115234375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.1700000000000000122124532708767219446599483489990234375,
            "max_sog": 0.5
        }
    },
    "time_window": {
        "start": "2026-10-23T05:12:49+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 19,
        "vessel_b": 19
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 85,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 289m, avg 292m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 204 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 289m, avg 292m) for 204 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 05:12 UTC 75.0% ▼

Duration: 6 hours
Radius: 5 meters
Data Points: 15 AIS positions
Centroid: 46.6198, 142.8995
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 4.79999999999999982236431605997495353221893310546875,
    "duration_minutes": 360,
    "points": 15,
    "centroid": {
        "lat": 46.61975022666667456405775737948715686798095703125,
        "lon": 142.8994788866666567628271877765655517578125
    },
    "bbox": {
        "min_lat": 46.61971330000000079962774179875850677490234375,
        "min_lon": 142.8994500000000016370904631912708282470703125,
        "max_lat": 46.619793299999997771010384894907474517822265625,
        "max_lon": 142.899489999999985911927069537341594696044921875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 05:12 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6 hours
Data Points: 15 AIS positions
Period: 2026-10-23T05:12:11+00:00 to 2026-10-23T11:12:11+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 360,
    "points_in_zone": 15,
    "first_point": {
        "ts": "2026-10-23T05:12:11+00:00",
        "lat": 46.61978669999999880246832617558538913726806640625,
        "lon": 142.899484999999998535713530145585536956787109375
    },
    "last_point": {
        "ts": "2026-10-23T11:12:11+00:00",
        "lat": 46.6197700000000025966073735617101192474365234375,
        "lon": 142.899454999999989013304002583026885986328125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 05:08 UTC 75.0% ▼

Duration: 6h 34m
Radius: 93 meters
Data Points: 48 AIS positions
Centroid: 46.6141, 142.5300
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 92.5,
    "duration_minutes": 394.3999999999999772626324556767940521240234375,
    "points": 48,
    "centroid": {
        "lat": 46.614059168750003436798579059541225433349609375,
        "lon": 142.529979235416618621457018889486789703369140625
    },
    "bbox": {
        "min_lat": 46.61364999999999980673237587325274944305419921875,
        "min_lon": 142.52906500000000278305378742516040802001953125,
        "max_lat": 46.61460329999999885330908000469207763671875,
        "max_lon": 142.53028169999998908679117448627948760986328125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 05:08 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 34m
Data Points: 48 AIS positions
Period: 2026-10-23T05:44:41+00:00 to 2026-10-23T12:19:04+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 394.3999999999999772626324556767940521240234375,
    "points_in_zone": 48,
    "first_point": {
        "ts": "2026-10-23T05:44:41+00:00",
        "lat": 46.61364999999999980673237587325274944305419921875,
        "lon": 142.53028169999998908679117448627948760986328125
    },
    "last_point": {
        "ts": "2026-10-23T12:19:04+00:00",
        "lat": 46.61395999999999872898115427233278751373291015625,
        "lon": 142.530043299999988448689691722393035888671875
    }
}

Methodology: 2026.01.18

Sts Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 05:04 UTC 95/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 9 meters
Average Distance: 12 meters
Duration: 3h 15m
Period: 2026-10-23T05:21:49+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.0 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 95/100

High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 9m, avg 12m) for 195 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 9m, avg 12m
Duration	25/25	Duration 195 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 8.9000000000000003552713678800500929355621337890625,
    "avg_distance_m": 11.699999999999999289457264239899814128875732421875,
    "distance_consistency_m": 1.3000000000000000444089209850062616169452667236328125,
    "duration_minutes": 195,
    "overlap_duration_s": 11701,
    "speed_a_avg": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.1499999999999999944488848768742172978818416595458984375,
    "speed_b_std": 0.11999999999999999555910790149937383830547332763671875,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.040000000000000000832667268468867405317723751068115234375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.1499999999999999944488848768742172978818416595458984375,
            "max_sog": 0.40000000000000002220446049250313080847263336181640625
        }
    },
    "time_window": {
        "start": "2026-10-23T05:21:49+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 18,
        "vessel_b": 18
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 95,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 9m, avg 12m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 195 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 9m, avg 12m) for 195 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 05:03 UTC 75.0% ▼

Duration: 3h 33m
Radius: 4 meters
Data Points: 21 AIS positions
Centroid: 46.6241, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 4,
    "duration_minutes": 213,
    "points": 21,
    "centroid": {
        "lat": 46.6240809476190491977831698022782802581787109375,
        "lon": 142.7691156619047205822425894439220428466796875
    },
    "bbox": {
        "min_lat": 46.6240667000000001962689566425979137420654296875,
        "min_lon": 142.769100000000008776623872108757495880126953125,
        "max_lat": 46.62411670000000185609678737819194793701171875,
        "max_lon": 142.7691317000000026382622309029102325439453125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 05:03 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 3h 33m
Data Points: 21 AIS positions
Period: 2026-10-23T05:03:48+00:00 to 2026-10-23T08:36:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 213,
    "points_in_zone": 21,
    "first_point": {
        "ts": "2026-10-23T05:03:48+00:00",
        "lat": 46.6240667000000001962689566425979137420654296875,
        "lon": 142.769116700000012087912182323634624481201171875
    },
    "last_point": {
        "ts": "2026-10-23T08:36:50+00:00",
        "lat": 46.62408330000000233894752454943954944610595703125,
        "lon": 142.7691317000000026382622309029102325439453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 05:01 UTC 75.0% ▼

Duration: 6h 33m
Radius: 59 meters
Data Points: 37 AIS positions
Centroid: 46.5363, 142.9392
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 59.2999999999999971578290569595992565155029296875,
    "duration_minutes": 393,
    "points": 37,
    "centroid": {
        "lat": 46.53629247567567261967269587330520153045654296875,
        "lon": 142.9392088729729266560752876102924346923828125
    },
    "bbox": {
        "min_lat": 46.53606500000000067984728957526385784149169921875,
        "min_lon": 142.938573300000001609078026376664638519287109375,
        "max_lat": 46.53659669999999692890924052335321903228759765625,
        "max_lon": 142.9397066999999879044480621814727783203125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 05:01 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 33m
Data Points: 37 AIS positions
Period: 2026-10-23T05:52:51+00:00 to 2026-10-23T12:25:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 393,
    "points_in_zone": 37,
    "first_point": {
        "ts": "2026-10-23T05:52:51+00:00",
        "lat": 46.53615330000000227528289542533457279205322265625,
        "lon": 142.939478299999990440483088605105876922607421875
    },
    "last_point": {
        "ts": "2026-10-23T12:25:50+00:00",
        "lat": 46.5364833000000004403773345984518527984619140625,
        "lon": 142.93878499999999576175468973815441131591796875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 05:01 UTC 75.0% ▼

Duration: 3h 47m
Radius: 2 meters
Data Points: 56 AIS positions
Centroid: 46.6240, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.600000000000000088817841970012523233890533447265625,
    "duration_minutes": 227.19999999999998863131622783839702606201171875,
    "points": 56,
    "centroid": {
        "lat": 46.6239777089285780675709247589111328125,
        "lon": 142.76912973571421616725274361670017242431640625
    },
    "bbox": {
        "min_lat": 46.6239632999999997764462023042142391204833984375,
        "min_lon": 142.76911169999999628998921252787113189697265625,
        "max_lat": 46.62398830000000060636011767201125621795654296875,
        "max_lon": 142.769141700000005812398740090429782867431640625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 05:01 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 3h 47m
Data Points: 56 AIS positions
Period: 2026-10-23T05:01:49+00:00 to 2026-10-23T08:49:03+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 227.19999999999998863131622783839702606201171875,
    "points_in_zone": 56,
    "first_point": {
        "ts": "2026-10-23T05:01:49+00:00",
        "lat": 46.6239800000000030877345125190913677215576171875,
        "lon": 142.769133299999992914308677427470684051513671875
    },
    "last_point": {
        "ts": "2026-10-23T08:49:03+00:00",
        "lat": 46.6239632999999997764462023042142391204833984375,
        "lon": 142.769126699999986840339261107146739959716796875
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach GALAXY (IMO: 9826902, MMSI: 461000329)

Oct 23, 2026 05:00 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 7m
Data Points: 41 AIS positions
Period: 2026-10-23T05:00:22+00:00 to 2026-10-23T11:07:51+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 367.5,
    "points_in_zone": 41,
    "first_point": {
        "ts": "2026-10-23T05:00:22+00:00",
        "lat": 46.3465249999999997498889570124447345733642578125,
        "lon": 142.857613299999997025224729441106319427490234375
    },
    "last_point": {
        "ts": "2026-10-23T11:07:51+00:00",
        "lat": 46.30786499999999961119101499207317829132080078125,
        "lon": 142.819081699999998136263457126915454864501953125
    }
}

Methodology: 2026.01.18

Sts Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 04:55 UTC 85/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Minimum Distance: 289 meters
Average Distance: 291 meters
Duration: 4h 24m
Period: 2026-10-23T04:12:48+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.0 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 85/100

High-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 289m, avg 291m) for 264 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 289m, avg 291m
Duration	25/25	Duration 264 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "min_distance_m": 288.8999999999999772626324556767940521240234375,
    "avg_distance_m": 291.3999999999999772626324556767940521240234375,
    "distance_consistency_m": 1.100000000000000088817841970012523233890533447265625,
    "duration_minutes": 264,
    "overlap_duration_s": 15842,
    "speed_a_avg": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.190000000000000002220446049250313080847263336181640625,
    "speed_b_std": 0.13000000000000000444089209850062616169452667236328125,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.040000000000000000832667268468867405317723751068115234375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.190000000000000002220446049250313080847263336181640625,
            "max_sog": 0.5
        }
    },
    "time_window": {
        "start": "2026-10-23T04:12:48+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 26,
        "vessel_b": 26
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 85,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 289m, avg 291m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 264 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and ZAPRAVSHCHIK 05) maintained close proximity (min 289m, avg 291m) for 264 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    }
}

Methodology: 2026.01.18

Sts Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 04:50 UTC 95/100 ▼

Vessel A: IMO 8135215 (FLAGMAN) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 9 meters
Average Distance: 11 meters
Duration: 4h 24m
Period: 2026-10-23T04:12:48+00:00 to 2026-10-23T08:36:50+00:00
Vessel A Avg Speed: 0.0 knots
Vessel B Avg Speed: 0.2 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 95/100

High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 9m, avg 11m) for 264 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 9m, avg 11m
Duration	25/25	Duration 264 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273443820,
        "imo": 8135215,
        "name": "FLAGMAN",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 8.9000000000000003552713678800500929355621337890625,
    "avg_distance_m": 11.4000000000000003552713678800500929355621337890625,
    "distance_consistency_m": 1.399999999999999911182158029987476766109466552734375,
    "duration_minutes": 264,
    "overlap_duration_s": 15842,
    "speed_a_avg": 0.040000000000000000832667268468867405317723751068115234375,
    "speed_a_std": 0.05000000000000000277555756156289135105907917022705078125,
    "speed_b_avg": 0.1600000000000000033306690738754696212708950042724609375,
    "speed_b_std": 0.11000000000000000055511151231257827021181583404541015625,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.040000000000000000832667268468867405317723751068115234375,
            "max_sog": 0.1000000000000000055511151231257827021181583404541015625
        },
        "vessel_b": {
            "avg_sog": 0.1600000000000000033306690738754696212708950042724609375,
            "max_sog": 0.40000000000000002220446049250313080847263336181640625
        }
    },
    "time_window": {
        "start": "2026-10-23T04:12:48+00:00",
        "end": "2026-10-23T08:36:50+00:00"
    },
    "points_count": {
        "vessel_a": 26,
        "vessel_b": 26
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 95,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 9m, avg 11m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 264 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (FLAGMAN and AZOV) maintained close proximity (min 9m, avg 11m) for 264 minutes. Both vessels were slow-moving (avg speeds 0.0 and 0.2 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 04:26 UTC 75.0% ▼

Duration: 6h 36m
Radius: 101 meters
Data Points: 43 AIS positions
Centroid: 46.6140, 142.5300
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 101,
    "duration_minutes": 396.3999999999999772626324556767940521240234375,
    "points": 43,
    "centroid": {
        "lat": 46.61397492325581737304673879407346248626708984375,
        "lon": 142.53001666976746264481334947049617767333984375
    },
    "bbox": {
        "min_lat": 46.613411700000000337240635417401790618896484375,
        "min_lon": 142.52906500000000278305378742516040802001953125,
        "max_lat": 46.61460329999999885330908000469207763671875,
        "max_lon": 142.530364999999989095158525742590427398681640625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach OMSK (IMO: 9418509, MMSI: 273371330)

Oct 23, 2026 04:26 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 36m
Data Points: 43 AIS positions
Period: 2026-10-23T04:50:41+00:00 to 2026-10-23T11:27:04+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 396.3999999999999772626324556767940521240234375,
    "points_in_zone": 43,
    "first_point": {
        "ts": "2026-10-23T04:50:41+00:00",
        "lat": 46.6135799999999989040588843636214733123779296875,
        "lon": 142.53032500000000482032191939651966094970703125
    },
    "last_point": {
        "ts": "2026-10-23T11:27:04+00:00",
        "lat": 46.61410500000000212139639188535511493682861328125,
        "lon": 142.530049999999988585841492749750614166259765625
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 04:25 UTC 75.0% ▼

Duration: 4h 26m
Radius: 87 meters
Data Points: 13 AIS positions
Centroid: 46.6492, 142.5429
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 86.900000000000005684341886080801486968994140625,
    "duration_minutes": 266.1000000000000227373675443232059478759765625,
    "points": 13,
    "centroid": {
        "lat": 46.64918976153845875387560226954519748687744140625,
        "lon": 142.5429461538461737291072495281696319580078125
    },
    "bbox": {
        "min_lat": 46.6484166999999985137037583626806735992431640625,
        "min_lon": 142.542633300000005647234502248466014862060546875,
        "max_lat": 46.649716699999999036663211882114410400390625,
        "max_lon": 142.543116700000012997406884096562862396240234375
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 04:25 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 26m
Data Points: 13 AIS positions
Period: 2026-10-23T04:25:59+00:00 to 2026-10-23T08:52:02+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 266.1000000000000227373675443232059478759765625,
    "points_in_zone": 13,
    "first_point": {
        "ts": "2026-10-23T04:25:59+00:00",
        "lat": 46.6484166999999985137037583626806735992431640625,
        "lon": 142.543116700000012997406884096562862396240234375
    },
    "last_point": {
        "ts": "2026-10-23T08:52:02+00:00",
        "lat": 46.649716699999999036663211882114410400390625,
        "lon": 142.542633300000005647234502248466014862060546875
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach BUKHTA NAGAEVA (IMO: 9183817, MMSI: 273219140)

Oct 23, 2026 04:25 UTC 92/100 ▼

Vessel A: IMO 9183817 (BUKHTA NAGAEVA) RUSSIA

Vessel B: SOLARIS (SOLARIS) OMAN

Minimum Distance: 43 meters
Average Distance: 147 meters
Duration: 4h 18m
Period: 2026-10-23T04:25:59+00:00 to 2026-10-23T08:44:54+00:00
Vessel A Avg Speed: 0.1 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 92/100

High-confidence STS candidate. Two tankers (BUKHTA NAGAEVA and SOLARIS) maintained close proximity (min 43m, avg 147m) for 259 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	25/25	Min distance 43m, avg 147m
Duration	25/25	Duration 259 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	12/15	Distance variance ±50m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T10:45:10.431778+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273219140,
        "imo": 9183817,
        "name": "BUKHTA NAGAEVA",
        "flag": "RUSSIA"
    },
    "vessel_b": {
        "mmsi": 461000248,
        "imo": 9333436,
        "name": "SOLARIS",
        "flag": "OMAN"
    },
    "min_distance_m": 42.89999999999999857891452847979962825775146484375,
    "avg_distance_m": 147.30000000000001136868377216160297393798828125,
    "distance_consistency_m": 49.89999999999999857891452847979962825775146484375,
    "duration_minutes": 258.8999999999999772626324556767940521240234375,
    "overlap_duration_s": 15535,
    "speed_a_avg": 0.070000000000000006661338147750939242541790008544921875,
    "speed_a_std": 0.0899999999999999966693309261245303787291049957275390625,
    "speed_b_avg": 0.13000000000000000444089209850062616169452667236328125,
    "speed_b_std": 0.11000000000000000055511151231257827021181583404541015625,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.070000000000000006661338147750939242541790008544921875,
            "max_sog": 0.299999999999999988897769753748434595763683319091796875
        },
        "vessel_b": {
            "avg_sog": 0.13000000000000000444089209850062616169452667236328125,
            "max_sog": 0.40000000000000002220446049250313080847263336181640625
        }
    },
    "time_window": {
        "start": "2026-10-23T04:25:59+00:00",
        "end": "2026-10-23T08:44:54+00:00"
    },
    "points_count": {
        "vessel_a": 12,
        "vessel_b": 12
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 92,
        "components": {
            "distance_tightness": {
                "score": 25,
                "max": 25,
                "detail": "Min distance 43m, avg 147m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 259 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 12,
                "max": 15,
                "detail": "Distance variance \u00b150m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (BUKHTA NAGAEVA and SOLARIS) maintained close proximity (min 43m, avg 147m) for 259 minutes. Both vessels were slow-moving (avg speeds 0.1 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.64946809999999999263309291563928127288818359375,
            "lon": 142.542810400000007575727067887783050537109375
        },
        "time_window": {
            "start_ts": "2026-10-23T04:25:59+00:00",
            "end_ts": "2026-10-23T08:44:54+00:00"
        },
        "searched_at": "2026-10-23T10:45:10.431778+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 04:12 UTC 75.0% ▼

Duration: 4h 24m
Radius: 4 meters
Data Points: 26 AIS positions
Centroid: 46.6241, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 4.20000000000000017763568394002504646778106689453125,
    "duration_minutes": 264,
    "points": 26,
    "centroid": {
        "lat": 46.62407884230768928546240204013884067535400390625,
        "lon": 142.7691145769230161022278480231761932373046875
    },
    "bbox": {
        "min_lat": 46.6240499999999968849806464277207851409912109375,
        "min_lon": 142.769100000000008776623872108757495880126953125,
        "max_lat": 46.62411670000000185609678737819194793701171875,
        "max_lon": 142.7691317000000026382622309029102325439453125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach FLAGMAN (IMO: 8135215, MMSI: 273443820)

Oct 23, 2026 04:12 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 24m
Data Points: 26 AIS positions
Period: 2026-10-23T04:12:48+00:00 to 2026-10-23T08:36:50+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 264,
    "points_in_zone": 26,
    "first_point": {
        "ts": "2026-10-23T04:12:48+00:00",
        "lat": 46.62408330000000233894752454943954944610595703125,
        "lon": 142.769116700000012087912182323634624481201171875
    },
    "last_point": {
        "ts": "2026-10-23T08:36:50+00:00",
        "lat": 46.62408330000000233894752454943954944610595703125,
        "lon": 142.7691317000000026382622309029102325439453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 04:10 UTC 75.0% ▼

Duration: 4h 32m
Radius: 1 meters
Data Points: 37 AIS positions
Centroid: 46.6256, 142.7660
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.3000000000000000444089209850062616169452667236328125,
    "duration_minutes": 272,
    "points": 37,
    "centroid": {
        "lat": 46.62555351891892740923140081577003002166748046875,
        "lon": 142.765967254054061186252511106431484222412109375
    },
    "bbox": {
        "min_lat": 46.6255450000000024601831682957708835601806640625,
        "min_lon": 142.765958299999994096651789732277393341064453125,
        "max_lat": 46.62556500000000170302882906980812549591064453125,
        "max_lon": 142.76597670000001016887836158275604248046875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 04:10 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 32m
Data Points: 37 AIS positions
Period: 2026-10-23T04:10:45+00:00 to 2026-10-23T08:42:46+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 272,
    "points_in_zone": 37,
    "first_point": {
        "ts": "2026-10-23T04:10:45+00:00",
        "lat": 46.62554999999999694182406528852880001068115234375,
        "lon": 142.765971699999994370955391786992549896240234375
    },
    "last_point": {
        "ts": "2026-10-23T08:42:46+00:00",
        "lat": 46.62555669999999707897586631588637828826904296875,
        "lon": 142.765974999999997407940099947154521942138671875
    }
}

Methodology: 2026.01.18

Sts🛰️✗ Sakhalin South Approach ZAPRAVSHCHIK 05 (IMO: 8930744, MMSI: 273439180)

Oct 23, 2026 04:10 UTC 85/100 ▼

Vessel A: IMO 8930744 (ZAPRAVSHCHIK 05) Russia

Vessel B: IMO 9084401 (AZOV) Russia

Minimum Distance: 298 meters
Average Distance: 299 meters
Duration: 4h 32m
Period: 2026-10-23T04:10:45+00:00 to 2026-10-23T08:42:46+00:00
Vessel A Avg Speed: 0.2 knots
Vessel B Avg Speed: 0.1 knots
Zone: Sakhalin South Approach

Confidence Analysis

Score: 85/100

High-confidence STS candidate. Two tankers (ZAPRAVSHCHIK 05 and AZOV) maintained close proximity (min 298m, avg 299m) for 272 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area.

View scoring breakdown

Factor	Score	Detail
Distance Tightness	15/25	Min distance 298m, avg 299m
Duration	25/25	Duration 272 minutes
Speed Stability	20/20	both nearly stationary; very stable speeds
Distance Consistency	15/15	Distance variance ±1m
Isolation	5/10	Isolation data not available
Context	5/5	In monitored zone: Sakhalin South Approach

🛰️ Satellite Corroboration

✗ SAR Not Available

No satellite imagery for this time/location

No Sentinel-1 scenes covering AOI and time window

Searched: 2026-10-23T10:45:05.440266+00:00

Show Raw Evidence JSON

{
    "vessel_a": {
        "mmsi": 273439180,
        "imo": 8930744,
        "name": "ZAPRAVSHCHIK 05",
        "flag": "Russia"
    },
    "vessel_b": {
        "mmsi": 273456730,
        "imo": 9084401,
        "name": "AZOV",
        "flag": "Russia"
    },
    "min_distance_m": 297.69999999999998863131622783839702606201171875,
    "avg_distance_m": 299,
    "distance_consistency_m": 0.6999999999999999555910790149937383830547332763671875,
    "duration_minutes": 272,
    "overlap_duration_s": 16321,
    "speed_a_avg": 0.190000000000000002220446049250313080847263336181640625,
    "speed_a_std": 0.13000000000000000444089209850062616169452667236328125,
    "speed_b_avg": 0.11000000000000000055511151231257827021181583404541015625,
    "speed_b_std": 0.11000000000000000055511151231257827021181583404541015625,
    "speed_summary": {
        "vessel_a": {
            "avg_sog": 0.190000000000000002220446049250313080847263336181640625,
            "max_sog": 0.5
        },
        "vessel_b": {
            "avg_sog": 0.11000000000000000055511151231257827021181583404541015625,
            "max_sog": 0.299999999999999988897769753748434595763683319091796875
        }
    },
    "time_window": {
        "start": "2026-10-23T04:10:45+00:00",
        "end": "2026-10-23T08:42:46+00:00"
    },
    "points_count": {
        "vessel_a": 37,
        "vessel_b": 37
    },
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "score": {
        "value": 85,
        "components": {
            "distance_tightness": {
                "score": 15,
                "max": 25,
                "detail": "Min distance 298m, avg 299m"
            },
            "duration": {
                "score": 25,
                "max": 25,
                "detail": "Duration 272 minutes"
            },
            "speed_stability": {
                "score": 20,
                "max": 20,
                "detail": "both nearly stationary; very stable speeds"
            },
            "distance_consistency": {
                "score": 15,
                "max": 15,
                "detail": "Distance variance \u00b11m"
            },
            "isolation": {
                "score": 5,
                "max": 10,
                "detail": "Isolation data not available"
            },
            "context": {
                "score": 5,
                "max": 5,
                "detail": "In monitored zone: Sakhalin South Approach"
            }
        },
        "summary": "High-confidence STS candidate. Two tankers (ZAPRAVSHCHIK 05 and AZOV) maintained close proximity (min 298m, avg 299m) for 272 minutes. Both vessels were slow-moving (avg speeds 0.2 and 0.1 knots). The stable separation distance suggests deliberate parallel positioning typical of cargo transfer. Event occurred in Sakhalin South Approach, a known STS activity area."
    },
    "sar": {
        "status": "not_found",
        "centroid": {
            "lat": 46.6247656999999975369064486585557460784912109375,
            "lon": 142.7675490999999965424649417400360107421875
        },
        "time_window": {
            "start_ts": "2026-10-23T04:10:45+00:00",
            "end_ts": "2026-10-23T08:42:46+00:00"
        },
        "searched_at": "2026-10-23T10:45:05.440266+00:00",
        "notes": "No Sentinel-1 scenes covering AOI and time window"
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 04:09 UTC 75.0% ▼

Duration: 6h 24m
Radius: 5 meters
Data Points: 16 AIS positions
Centroid: 46.6198, 142.8995
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 4.79999999999999982236431605997495353221893310546875,
    "duration_minutes": 384,
    "points": 16,
    "centroid": {
        "lat": 46.6197500062500012063537724316120147705078125,
        "lon": 142.89947875000001431544660590589046478271484375
    },
    "bbox": {
        "min_lat": 46.61971330000000079962774179875850677490234375,
        "min_lon": 142.8994500000000016370904631912708282470703125,
        "max_lat": 46.619793299999997771010384894907474517822265625,
        "max_lon": 142.899489999999985911927069537341594696044921875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PACIFIC ARCADIA (IMO: 9621077, MMSI: 311072200)

Oct 23, 2026 04:09 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 24m
Data Points: 16 AIS positions
Period: 2026-10-23T04:48:13+00:00 to 2026-10-23T11:12:11+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 384,
    "points_in_zone": 16,
    "first_point": {
        "ts": "2026-10-23T04:48:13+00:00",
        "lat": 46.61974670000000031677700462751090526580810546875,
        "lon": 142.899476700000008122515282593667507171630859375
    },
    "last_point": {
        "ts": "2026-10-23T11:12:11+00:00",
        "lat": 46.6197700000000025966073735617101192474365234375,
        "lon": 142.899454999999989013304002583026885986328125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 04:07 UTC 75.0% ▼

Duration: 4h 38m
Radius: 436 meters
Data Points: 30 AIS positions
Centroid: 46.6497, 142.5426
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 436.30000000000001136868377216160297393798828125,
    "duration_minutes": 278.80000000000001136868377216160297393798828125,
    "points": 30,
    "centroid": {
        "lat": 46.6496649999999846158971195109188556671142578125,
        "lon": 142.5426261100000147052924148738384246826171875
    },
    "bbox": {
        "min_lat": 46.6459167000000007874405127950012683868408203125,
        "min_lon": 142.540249999999986130205797962844371795654296875,
        "max_lat": 46.6522666999999984227542881853878498077392578125,
        "max_lon": 142.544516700000002629167283885180950164794921875
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach SOLARIS (IMO: 9333436, MMSI: 461000248)

Oct 23, 2026 04:07 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 38m
Data Points: 30 AIS positions
Period: 2026-10-23T04:07:22+00:00 to 2026-10-23T08:46:08+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 278.80000000000001136868377216160297393798828125,
    "points_in_zone": 30,
    "first_point": {
        "ts": "2026-10-23T04:07:22+00:00",
        "lat": 46.6459167000000007874405127950012683868408203125,
        "lon": 142.544316699999995989855960942804813385009765625
    },
    "last_point": {
        "ts": "2026-10-23T08:46:08+00:00",
        "lat": 46.65008329999999858728187973611056804656982421875,
        "lon": 142.5409832999999935054802335798740386962890625
    }
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach GALAXY (IMO: 9826902, MMSI: 461000329)

Oct 23, 2026 04:06 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 33m
Data Points: 45 AIS positions
Period: 2026-10-23T04:34:23+00:00 to 2026-10-23T11:07:51+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 393.5,
    "points_in_zone": 45,
    "first_point": {
        "ts": "2026-10-23T04:34:23+00:00",
        "lat": 46.33652169999999870242390898056328296661376953125,
        "lon": 142.846148300000010067378752864897251129150390625
    },
    "last_point": {
        "ts": "2026-10-23T11:07:51+00:00",
        "lat": 46.30786499999999961119101499207317829132080078125,
        "lon": 142.819081699999998136263457126915454864501953125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 04:04 UTC 75.0% ▼

Duration: 4h 44m
Radius: 2 meters
Data Points: 70 AIS positions
Centroid: 46.6240, 142.7691
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 1.600000000000000088817841970012523233890533447265625,
    "duration_minutes": 284.3999999999999772626324556767940521240234375,
    "points": 70,
    "centroid": {
        "lat": 46.62397726285713162042156909592449665069580078125,
        "lon": 142.76913047714288040879182517528533935546875
    },
    "bbox": {
        "min_lat": 46.6239632999999997764462023042142391204833984375,
        "min_lon": 142.76911169999999628998921252787113189697265625,
        "max_lat": 46.62398830000000060636011767201125621795654296875,
        "max_lon": 142.769141700000005812398740090429782867431640625
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach AZOV (IMO: 9084401, MMSI: 273456730)

Oct 23, 2026 04:04 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 4h 44m
Data Points: 70 AIS positions
Period: 2026-10-23T04:04:38+00:00 to 2026-10-23T08:49:03+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 284.3999999999999772626324556767940521240234375,
    "points_in_zone": 70,
    "first_point": {
        "ts": "2026-10-23T04:04:38+00:00",
        "lat": 46.623975000000001500666257925331592559814453125,
        "lon": 142.769133299999992914308677427470684051513671875
    },
    "last_point": {
        "ts": "2026-10-23T08:49:03+00:00",
        "lat": 46.6239632999999997764462023042142391204833984375,
        "lon": 142.769126699999986840339261107146739959716796875
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 04:02 UTC 75.0% ▼

Duration: 6h 31m
Radius: 65 meters
Data Points: 31 AIS positions
Centroid: 46.6921, 142.5762
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 65.400000000000005684341886080801486968994140625,
    "duration_minutes": 391.80000000000001136868377216160297393798828125,
    "points": 31,
    "centroid": {
        "lat": 46.69214602258062996043008752167224884033203125,
        "lon": 142.576218383870951811331906355917453765869140625
    },
    "bbox": {
        "min_lat": 46.69163999999999958845364744774997234344482421875,
        "min_lon": 142.57553999999998950443114154040813446044921875,
        "max_lat": 46.6926150000000035333869163878262042999267578125,
        "max_lon": 142.5765083000000004176399670541286468505859375
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Zone Dwell Sakhalin South Approach PHOENIX II (IMO: 8603638, MMSI: 273356770)

Oct 23, 2026 04:02 UTC 80.0% ▼

Zone: Sakhalin South Approach
Duration: 6h 31m
Data Points: 31 AIS positions
Period: 2026-10-23T04:23:45+00:00 to 2026-10-23T10:55:31+00:00

Show Raw Evidence JSON

{
    "zone_id": "russia_sakhalin_south",
    "zone_name": "Sakhalin South Approach",
    "dwell_minutes": 391.80000000000001136868377216160297393798828125,
    "points_in_zone": 31,
    "first_point": {
        "ts": "2026-10-23T04:23:45+00:00",
        "lat": 46.69213669999999893889253144152462482452392578125,
        "lon": 142.5761932999999999083229340612888336181640625
    },
    "last_point": {
        "ts": "2026-10-23T10:55:31+00:00",
        "lat": 46.69258330000000256632119999267160892486572265625,
        "lon": 142.576019999999999754436430521309375762939453125
    }
}

Methodology: 2026.01.18

Loiter Sakhalin South Approach ZALIV ANIVA (IMO: 9418494, MMSI: 461000231)

Oct 23, 2026 04:01 UTC 75.0% ▼

Duration: 6h 33m
Radius: 72 meters
Data Points: 45 AIS positions
Centroid: 46.5362, 142.9393
Zone: Sakhalin South Approach

Show Raw Evidence JSON

{
    "radius_m": 71.7000000000000028421709430404007434844970703125,
    "duration_minutes": 393,
    "points": 45,
    "centroid": {
        "lat": 46.5362291466666562200771295465528964996337890625,
        "lon": 142.939340773333327661021030507981777191162109375
    },
    "bbox": {
        "min_lat": 46.53606500000000067984728957526385784149169921875,
        "min_lon": 142.938573300000001609078026376664638519287109375,
        "max_lat": 46.53659669999999692890924052335321903228759765625,
        "max_lon": 142.9397066999999879044480621814727783203125
    },
    "zone_id": "russia_sakhalin_south"
}

Methodology: 2026.01.18

Maritime Risk Signals

Sakhalin South Approach

📝 Notes

Confidence Analysis

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🛰️ Satellite Corroboration

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🛰️ Satellite Corroboration

Confidence Analysis

🛰️ Satellite Corroboration

Confidence Analysis

Confidence Analysis

Confidence Analysis

Confidence Analysis

Confidence Analysis

Confidence Analysis

🛰️ Satellite Corroboration

Confidence Analysis

🛰️ Satellite Corroboration

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