Kerch Strait
observingVessel (>=100 m) presence across the four-zone Kerch corridor, from Sentinel-1 radar imagery.
Dated measurements from fixed orbital calendars; readers draw their own conclusions. · Page updated 2026-08-07 00:43 (UTC)
The Sea of Azov has exactly one exit.
A real photograph, not a diagram: the shallow green Sea of Azov, the deep-blue Black Sea, and one narrow gap between them — the Kerch Strait. Every cargo of grain, steel and fuel from the Azov's ports passes through it.
Latest pass
The four zones — where the ships are
Every pass, the corridor’s ≥100 m detections are split into the four zones a transit chains through. Queues forming in staging with an empty transit span mean the gate is shut; everything draining at once means the ships left.
| pass | Azov staging | Transit span | Approach lane | Outer anchorage | total | quality |
|---|---|---|---|---|---|---|
| 2026-08-05 | ≥1 | ≥2 | ≥0 | ≥5 | ≥11 | banded — floors |
| 2026-07-30 | ≥1 | ≥0 | ≥0 | ≥0 | ≥3 | banded — floors |
| 2026-07-24 | ≥1 | ≥0 | ≥0 | ≥2 | ≥5 | banded — floors |
| 2026-07-18 | ≥1 | ≥4 | ≥0 | ≥4 | ≥11 | banded — floors |
| 2026-07-12 | ≥1 | ≥0 | ≥0 | ≥43 | ≥50 | banded — floors |
| 2026-07-06 | ≥21 | ≥0 | ≥0 | ≥71 | ≥111 | banded — floors |
| 2026-06-30 | ≥51 | ≥1 | ≥0 | ≥91 | ≥157 | banded — floors |
| 2026-06-23 | ≥35 | ≥0 | ≥0 | ≥95 | ≥139 | banded — floors |
| 2026-06-18 | ≥24 | ≥0 | ≥0 | ≥93 | ≥129 | banded — floors |
| 2026-06-11 | ≥25 | ≥3 | ≥1 | ≥106 | ≥156 | banded — floors |
| 2026-05-30 | ≥43 | ≥1 | ≥11 | ≥44 | ≥110 | banded — floors |
| 2026-05-25 | 54 | 0 | 0 | 102 | 173 | clean |
Newest 12 of 89 passes; the full series is in the record below. “≥” rows are banded passes: radar interference that day can hide ships, never invent them, so those counts are floors — and a rise on a floor is still a rise.
Method
Method and limits. Findings on this page are derived exclusively from publicly available satellite imagery (Copernicus Sentinel open data), analyzed after the imagery entered the public catalog. We publish counts and individual detections — position and approximate size — exactly as the instrument recorded them. Detections are anonymous: we never publish vessel identities or names, and we never track an individual vessel across dates, because the instrument cannot support those claims. Nothing we publish is fresher than the public availability of the underlying scene; the instrument observes on a fixed orbital calendar and cannot be tasked. Machine counts from radar imagery are approximate: interference bands can hide real vessels — never invent them — so banded dates are marked and their figures read as floors, and every count's measured error rates are published beside the data — image review calibrates those rates; it never silently corrects a number. Observations are dated — they describe what the instrument saw on the stated date. Corrections and revisions are shown, never silent.
Sentinel-1, relative orbit 94 · radar · ~03:39 UTC · 10 m/px
What this instrument sees: radar-bright hulls at one instant, vessels ≥100 m — pre-dawn, through cloud and darkness. What it cannot: vessels under 100 m, and on interference-banded dates its counts are floors, never levels. One row per satellite pass. Counts are after quality filtering (“gates”); see error notes below.
Count over time
2025-012025-052025-082025-122026-042026-08
Daily ≥100 m machine count across the series (2025-01-11 → 2026-08-05, peak 322). One point per pass; the line is linear between passes, not interpolated data. Hollow points are banded passes: their counts are floors (“at least N”), never levels — radar interference hides ships, it does not invent them.
Where it's pointed
2026-08-05 · pass 89 of 89 · 11 detections ≥100 m
200–300 m≥300 mdot = one machine detection · position + size class only · no identities, no tracks
What this instrument can and cannot do
- The Kerch Strait corridor is observed as a zone-level ≥100 m vessel-count sensor, trend-grade — four zones in chain order (outer anchorage → approach → transit span → Azov staging), radar imaging pre-dawn through cloud and darkness. Never a precise count, and no size class above ≥100 m is claimed (≥150/200 strata too thin to characterise).
- Measured error, both directions: contamination 0% [0–8/9%] (90% CI) in all three sea-state strata — 96 chips over two disjoint blind draws; kill-side zone-level loss ~0% with anchor-circle kills validated at 3% [1–13%] (kill1 blind draw, 52 chips). Adjudication is unanimous above peak-z ~150; fainter detections carry a mapped ambiguity class.
- Banded dates are floors, not levels. Radar interference bands crossed 46 of the 87 corpus dates; bands null real returns and never invent them, so a flagged date's count reads “≥N” and its sea-state reading is untrusted. Every record carries its measured band score and flag; flagged dates never enter change arithmetic.
- Known blind strip: a ~1.28 km band at the southern edge is unexamined on every date — constant per pass, so trends are unaffected. Four persistent Taman-bay radar signatures are cataloged and excluded (nature unknown; a matched-date optical walk found no vessel on any usable clear frame).
Error bands measured 2026-07-31 · last blind calibration 2026-07-31 (kill1) · 2 passes observed since (caveat at 4).
Full record & how we measure — every observation, calendar, error rates, revisions
Observations — every pass
| date | platform | ≥100 m | band score (dB) | sea VV median (dB) |
|---|---|---|---|---|
2026-08-05provenanceS1D_IW_GRDH_1SDV_20260805T033943_20260805T034008_003985_0073C9_rtc gates removed: 8 feature | S1D 03:39 | ≥11 | 11.2 banded | -18.4 (untrusted) |
2026-07-30provenanceS1C_IW_GRDH_1SDV_20260730T033929_20260730T033954_008767_011600_rtc · S1C_IW_GRDH_1SDV_20260730T033954_20260730T034019_008767_011600_rtc gates removed: 5 feature | S1C 03:39 | ≥3 | 19.7 banded | -16.8 (untrusted) |
2026-07-24provenanceS1D_IW_GRDH_1SDV_20260724T033943_20260724T034008_003810_006DAE_rtc gates removed: 6 feature | S1D 03:39 | ≥5 | 25.4 banded | -17.6 (untrusted) |
2026-07-18provenanceS1C_IW_GRDH_1SDV_20260718T033928_20260718T033953_008592_01103A_rtc · S1C_IW_GRDH_1SDV_20260718T033953_20260718T034018_008592_01103A_rtc gates removed: 7 feature | S1C 03:39 | ≥11 | 15.5 banded | -14.6 (untrusted) |
2026-07-12provenanceS1D_IW_GRDH_1SDV_20260712T033942_20260712T034007_003635_0067AC_rtc gates removed: 5 feature | S1D 03:39 | ≥50 | 15.9 banded | -17.5 (untrusted) |
2026-07-06provenanceS1C_IW_GRDH_1SDV_20260706T033927_20260706T033952_008417_010A72_rtc gates removed: 5 feature | S1C 03:39 | ≥111 | 13.4 banded | -16.1 (untrusted) |
2026-06-30provenanceS1D_IW_GRDH_1SDV_20260630T033941_20260630T034006_003460_0061C2_rtc gates removed: 5 feature | S1D 03:39 | ≥157 | 13.0 banded | -16.5 (untrusted) |
2026-06-23provenanceS1A_IW_GRDH_1SDV_20260623T034027_20260623T034052_065091_08345B_rtc gates removed: 6 feature | S1A 03:40 | ≥139 | 14.0 banded | -14.5 (untrusted) |
2026-06-18provenanceS1D_IW_GRDH_1SDV_20260618T033939_20260618T034004_003285_005BFE_rtc · S1D_IW_GRDH_1SDV_20260618T034004_20260618T034029_003285_005BFE_rtc gates removed: 7 feature | S1D 03:39 | ≥129 | 10.7 banded | -20.3 (untrusted) |
2026-06-11provenanceS1A_IW_GRDH_1SDV_20260611T034027_20260611T034052_064916_082E34_rtc gates removed: 7 feature | S1A 03:40 | ≥156 | 21.6 banded | -20.2 (untrusted) |
2026-05-30provenanceS1A_IW_GRDH_1SDV_20260530T034028_20260530T034053_064741_082816_rtc gates removed: 4 feature | S1A 03:40 | ≥110 | 16.8 banded | -16.6 (untrusted) |
2026-05-25provenanceS1D_IW_GRDH_1SDV_20260525T033937_20260525T034002_002935_005068_rtc · S1D_IW_GRDH_1SDV_20260525T034002_20260525T034027_002935_005068_rtc gates removed: 7 feature | S1D 03:39 | 173 | 1.8 | -18.2 |
2026-05-24provenanceS1C_IW_GRDH_1SDV_20260524T033928_20260524T033953_007790_00FD50_rtc · S1C_IW_GRDH_1SDV_20260524T033953_20260524T034018_007790_00FD50_rtc gates removed: 5 feature | S1C 03:39 | ≥118 | 12.9 banded | -18.3 (untrusted) |
2026-05-18provenanceS1A_IW_GRDH_1SDV_20260518T034029_20260518T034054_064566_0821F3_rtc gates removed: 9 feature | S1A 03:40 | 216 | 0.7 | -19.6 |
2026-05-13provenanceS1D_IW_GRDH_1SDV_20260513T033937_20260513T034002_002760_004A94_rtc · S1D_IW_GRDH_1SDV_20260513T034002_20260513T034027_002760_004A94_rtc gates removed: 7 feature | S1D 03:39 | 120 | 1.1 | -21.5 |
2026-05-06provenanceS1A_IW_GRDH_1SDV_20260506T034029_20260506T034054_064391_081BC3_rtc gates removed: 10 feature | S1A 03:40 | 218 | 3.7 | -23.6 |
2026-04-30provenanceS1C_IW_GRDH_1SDV_20260430T033926_20260430T033951_007440_00F18F_rtc · S1C_IW_GRDH_1SDV_20260430T033951_20260430T034016_007440_00F18F_rtc gates removed: 9 feature | S1C 03:39 | 145 | 2.7 | -20.0 |
2026-04-24provenanceS1A_IW_GRDH_1SDV_20260424T034030_20260424T034055_064216_081547_rtc gates removed: 8 feature | S1A 03:40 | 89 | 2.5 | -12.7 |
2026-04-18provenanceS1C_IW_GRDH_1SDV_20260418T033925_20260418T033950_007265_00EB9A_rtc · S1C_IW_GRDH_1SDV_20260418T033950_20260418T034015_007265_00EB9A_rtc gates removed: 8 feature | S1C 03:39 | 153 | 1.8 | -20.0 |
2026-04-12provenanceS1A_IW_GRDH_1SDV_20260412T034030_20260412T034055_064041_080EBE_rtc gates removed: 9 feature | S1A 03:40 | ≥133 | 9.4 banded | -21.9 (untrusted) |
2026-04-06provenanceS1C_IW_GRDH_1SDV_20260406T033925_20260406T033950_007090_00E5B7_rtc · S1C_IW_GRDH_1SDV_20260406T033950_20260406T034015_007090_00E5B7_rtc gates removed: 9 feature | S1C 03:39 | 163 | 1.3 | -23.1 |
2026-03-31provenanceS1A_IW_GRDH_1SDV_20260331T034029_20260331T034054_063866_08082E_rtc gates removed: 8 feature | S1A 03:40 | ≥139 | 9.9 banded | -19.9 (untrusted) |
2026-03-25provenanceS1C_IW_GRDH_1SDV_20260325T033924_20260325T033949_006915_00DFCC_rtc · S1C_IW_GRDH_1SDV_20260325T033949_20260325T034014_006915_00DFCC_rtc gates removed: 10 feature | S1C 03:39 | 158 | 1.4 | -17.7 |
2026-03-19provenanceS1A_IW_GRDH_1SDV_20260319T034029_20260319T034054_063691_0801AD_rtc gates removed: 10 feature | S1A 03:40 | 204 | 0.8 | -19.8 |
2026-03-13provenanceS1C_IW_GRDH_1SDV_20260313T033924_20260313T033949_006740_00D9D3_rtc · S1C_IW_GRDH_1SDV_20260313T033949_20260313T034014_006740_00D9D3_rtc gates removed: 6 feature | S1C 03:39 | 163 | 1.1 | -15.3 |
2026-03-07provenanceS1A_IW_GRDH_1SDV_20260307T034029_20260307T034054_063516_07FB21_rtc gates removed: 9 feature | S1A 03:40 | ≥216 | 7.9 banded | -18.9 (untrusted) |
2026-03-01provenanceS1C_IW_GRDH_1SDV_20260301T033924_20260301T033949_006565_00D3D2_rtc · S1C_IW_GRDH_1SDV_20260301T033949_20260301T034014_006565_00D3D2_rtc gates removed: 8 feature | S1C 03:39 | 230 | 1.8 | -22.3 |
2026-02-17provenanceS1C_IW_GRDH_1SDV_20260217T033924_20260217T033949_006390_00CDB7_rtc · S1C_IW_GRDH_1SDV_20260217T033949_20260217T034014_006390_00CDB7_rtc gates removed: 7 feature | S1C 03:39 | 212 | 1.3 | -19.0 |
2026-02-11provenanceS1A_IW_GRDH_1SDV_20260211T034030_20260211T034055_063166_07EDDB_rtc gates removed: 5 feature | S1A 03:40 | ≥168 | 21.2 banded | -13.1 (untrusted) |
2026-02-05provenanceS1C_IW_GRDH_1SDV_20260205T033924_20260205T033949_006215_00C7AA_rtc · S1C_IW_GRDH_1SDV_20260205T033949_20260205T034014_006215_00C7AA_rtc gates removed: 5 feature | S1C 03:39 | ≥212 | 8.7 banded | -12.5 (untrusted) |
2026-01-30provenanceS1A_IW_GRDH_1SDV_20260130T034031_20260130T034056_062991_07E753_rtc gates removed: 5 feature | S1A 03:40 | ≥244 | 13.8 banded | -19.1 (untrusted) |
2026-01-24provenanceS1C_IW_GRDH_1SDV_20260124T033924_20260124T033949_006040_00C1BF_rtc · S1C_IW_GRDH_1SDV_20260124T033949_20260124T034014_006040_00C1BF_rtc gates removed: 8 feature | S1C 03:39 | ≥186 | 14.4 banded | -17.7 (untrusted) |
2026-01-18provenanceS1A_IW_GRDH_1SDV_20260118T034031_20260118T034056_062816_07E10A_rtc gates removed: 6 feature | S1A 03:40 | ≥147 | 14.9 banded | -11.6 (untrusted) |
2026-01-12provenanceS1C_IW_GRDH_1SDV_20260112T033925_20260112T033950_005865_00BBFA_rtc · S1C_IW_GRDH_1SDV_20260112T033950_20260112T034015_005865_00BBFA_rtc gates removed: 6 feature | S1C 03:39 | ≥236 | 29.1 banded | -15.7 (untrusted) |
2026-01-06provenanceS1A_IW_GRDH_1SDV_20260106T034032_20260106T034057_062641_07DA4F_rtc gates removed: 9 feature | S1A 03:40 | ≥239 | 16.4 banded | -15.8 (untrusted) |
2025-12-31provenanceS1C_IW_GRDH_1SDV_20251231T033926_20251231T033951_005690_00B5D9_rtc · S1C_IW_GRDH_1SDV_20251231T033951_20251231T034016_005690_00B5D9_rtc gates removed: 5 feature | S1C 03:39 | ≥194 | 30.3 banded | -11.9 (untrusted) |
2025-12-25provenanceS1A_IW_GRDH_1SDV_20251225T034033_20251225T034058_062466_07D38B_rtc gates removed: 7 feature | S1A 03:40 | ≥287 | 30.7 banded | -16.4 (untrusted) |
2025-12-19provenanceS1C_IW_GRDH_1SDV_20251219T033926_20251219T033951_005515_00AFCA_rtc · S1C_IW_GRDH_1SDV_20251219T033951_20251219T034016_005515_00AFCA_rtc gates removed: 9 feature | S1C 03:39 | 290 | 1.4 | -25.7 |
2025-12-13provenanceS1A_IW_GRDH_1SDV_20251213T034035_20251213T034100_062291_07CCC2_rtc gates removed: 6 feature | S1A 03:40 | ≥125 | 11.2 banded | -9.4 (untrusted) |
2025-12-07provenanceS1C_IW_GRDH_1SDV_20251207T033927_20251207T033952_005340_00A9D1_rtc · S1C_IW_GRDH_1SDV_20251207T033952_20251207T034017_005340_00A9D1_rtc gates removed: 5 feature | S1C 03:39 | 134 | 0.8 | -10.1 |
2025-12-01provenanceS1A_IW_GRDH_1SDV_20251201T034036_20251201T034101_062116_07C5ED_rtc gates removed: 9 feature | S1A 03:40 | 170 | 1.2 | -17.9 |
2025-11-25provenanceS1C_IW_GRDH_1SDV_20251125T033927_20251125T033952_005165_00A3E9_rtc · S1C_IW_GRDH_1SDV_20251125T033952_20251125T034017_005165_00A3E9_rtc gates removed: 9 feature | S1C 03:39 | 193 | 1.4 | -23.8 |
2025-11-19provenanceS1A_IW_GRDH_1SDV_20251119T034037_20251119T034102_061941_07BF1A_rtc gates removed: 6 feature | S1A 03:40 | ≥233 | 14.6 banded | -19.4 (untrusted) |
2025-11-13provenanceS1C_IW_GRDH_1SDV_20251113T033928_20251113T033953_004990_009DFA_rtc · S1C_IW_GRDH_1SDV_20251113T033953_20251113T034018_004990_009DFA_rtc gates removed: 8 feature | S1C 03:39 | 268 | 1.8 | -17.9 |
2025-11-07provenanceS1A_IW_GRDH_1SDV_20251107T034038_20251107T034103_061766_07B84D_rtc gates removed: 8 feature | S1A 03:40 | 223 | 0.8 | -17.0 |
2025-11-01provenanceS1C_IW_GRDH_1SDV_20251101T033928_20251101T033953_004815_009830_rtc · S1C_IW_GRDH_1SDV_20251101T033953_20251101T034018_004815_009830_rtc gates removed: 5 feature | S1C 03:39 | ≥215 | 9.7 banded | -15.5 (untrusted) |
2025-10-26provenanceS1A_IW_GRDH_1SDV_20251026T034038_20251026T034103_061591_07B16B_rtc gates removed: 9 feature | S1A 03:40 | 199 | 4.0 | -20.6 |
2025-10-20provenanceS1C_IW_GRDH_1SDV_20251020T033929_20251020T033954_004640_0092C3_rtc · S1C_IW_GRDH_1SDV_20251020T033954_20251020T034019_004640_0092C3_rtc gates removed: 6 feature | S1C 03:39 | ≥196 | 26.8 banded | -12.4 (untrusted) |
2025-10-14provenanceS1A_IW_GRDH_1SDV_20251014T034038_20251014T034103_061416_07AA65_rtc gates removed: 9 feature | S1A 03:40 | 200 | 0.9 | -19.7 |
2025-10-08provenanceS1C_IW_GRDH_1SDV_20251008T033929_20251008T033954_004465_008D75_rtc · S1C_IW_GRDH_1SDV_20251008T033954_20251008T034019_004465_008D75_rtc gates removed: 5 feature | S1C 03:39 | ≥210 | 11.5 banded | -14.2 (untrusted) |
2025-10-02provenanceS1A_IW_GRDH_1SDV_20251002T034038_20251002T034103_061241_07A35C_rtc gates removed: 9 feature | S1A 03:40 | 237 | 0.9 | -20.2 |
2025-09-26provenanceS1C_IW_GRDH_1SDV_20250926T033928_20250926T033953_004290_00881F_rtc · S1C_IW_GRDH_1SDV_20250926T033953_20250926T034018_004290_00881F_rtc gates removed: 6 feature | S1C 03:39 | 282 | 1.1 | -14.3 |
2025-09-20provenanceS1A_IW_GRDH_1SDV_20250920T034038_20250920T034103_061066_079C48_rtc gates removed: 9 feature | S1A 03:40 | 243 | 0.8 | -17.7 |
2025-09-14provenanceS1C_IW_GRDH_1SDV_20250914T033928_20250914T033953_004115_0082D5_rtc · S1C_IW_GRDH_1SDV_20250914T033953_20250914T034018_004115_0082D5_rtc gates removed: 5 feature | S1C 03:39 | ≥170 | 13.1 banded | -11.7 (untrusted) |
2025-09-08provenanceS1A_IW_GRDH_1SDV_20250908T034038_20250908T034103_060891_079546_rtc gates removed: 8 feature | S1A 03:40 | 183 | 0.7 | -16.6 |
2025-09-02provenanceS1C_IW_GRDH_1SDV_20250902T033928_20250902T033953_003940_007D86_rtc · S1C_IW_GRDH_1SDV_20250902T033953_20250902T034018_003940_007D86_rtc gates removed: 8 feature | S1C 03:39 | 176 | 1.0 | -19.3 |
2025-08-27provenanceS1A_IW_GRDH_1SDV_20250827T034037_20250827T034102_060716_078E53_rtc gates removed: 9 feature | S1A 03:40 | 190 | 1.3 | -19.4 |
2025-08-21provenanceS1C_IW_GRDH_1SDV_20250821T033927_20250821T033952_003765_00783E_rtc · S1C_IW_GRDH_1SDV_20250821T033952_20250821T034017_003765_00783E_rtc gates removed: 7 feature | S1C 03:39 | 188 | 2.5 | -19.6 |
2025-08-15provenanceS1A_IW_GRDH_1SDV_20250815T034037_20250815T034102_060541_07876E_rtc gates removed: 9 feature | S1A 03:40 | 260 | 0.9 | -19.6 |
2025-08-09provenanceS1C_IW_GRDH_1SDV_20250809T033927_20250809T033952_003590_rtc · S1C_IW_GRDH_1SDV_20250809T033952_20250809T034017_003590_rtc gates removed: 4 feature | S1C 03:39 | ≥322 | 13.2 banded | -19.4 (untrusted) |
2025-08-03provenanceS1A_IW_GRDH_1SDV_20250803T034037_20250803T034102_060366_rtc gates removed: 8 feature | S1A 03:40 | 237 | 4.2 | -17.0 |
2025-07-28provenanceS1C_IW_GRDH_1SDV_20250728T033926_20250728T033951_003415_rtc · S1C_IW_GRDH_1SDV_20250728T033951_20250728T034016_003415_rtc gates removed: 4 feature | S1C 03:39 | ≥145 | 12.1 banded | -13.3 (untrusted) |
2025-07-22provenanceS1A_IW_GRDH_1SDV_20250722T034037_20250722T034102_060191_rtc gates removed: 5 feature | S1A 03:40 | ≥146 | 18.8 banded | -16.1 (untrusted) |
2025-07-16provenanceS1C_IW_GRDH_1SDV_20250716T033925_20250716T033950_003240_rtc · S1C_IW_GRDH_1SDV_20250716T033950_20250716T034015_003240_rtc gates removed: 4 feature | S1C 03:39 | ≥125 | 14.7 banded | -21.1 (untrusted) |
2025-07-10provenanceS1A_IW_GRDH_1SDV_20250710T034038_20250710T034103_060016_rtc gates removed: 8 feature | S1A 03:40 | 116 | 4.4 | -16.5 |
2025-07-04provenanceS1C_IW_GRDH_1SDV_20250704T033925_20250704T033950_003065_rtc · S1C_IW_GRDH_1SDV_20250704T033950_20250704T034015_003065_rtc gates removed: 7 feature | S1C 03:39 | 139 | 1.1 | -20.7 |
2025-06-28provenanceS1A_IW_GRDH_1SDV_20250628T034039_20250628T034104_059841_076EAC_rtc gates removed: 6 feature | S1A 03:40 | 125 | 3.9 | -17.5 |
2025-06-22provenanceS1C_IW_GRDH_1SDV_20250622T033924_20250622T033949_002890_rtc · S1C_IW_GRDH_1SDV_20250622T033949_20250622T034014_002890_rtc gates removed: 3 feature | S1C 03:39 | 107 | 0.9 | -18.8 |
2025-06-16provenanceS1A_IW_GRDH_1SDV_20250616T034039_20250616T034104_059666_07689A_rtc gates removed: 3 feature | S1A 03:40 | ≥147 | 12.0 banded | -15.2 (untrusted) |
2025-06-10provenanceS1C_IW_GRDH_1SDV_20250610T033923_20250610T033948_002715_rtc · S1C_IW_GRDH_1SDV_20250610T033948_20250610T034013_002715_rtc gates removed: 5 feature | S1C 03:39 | 159 | 1.0 | -21.6 |
2025-06-04provenanceS1A_IW_GRDH_1SDV_20250604T034040_20250604T034105_059491_rtc gates removed: 7 feature | S1A 03:40 | ≥154 | 9.6 banded | -16.7 (untrusted) |
2025-05-29provenanceS1C_IW_GRDH_1SDV_20250529T033923_20250529T033948_002540_rtc gates removed: 3 feature | S1C 03:39 | ≥107 | 15.3 banded | -21.9 (untrusted) |
2025-05-23provenanceS1A_IW_GRDH_1SDV_20250523T034040_20250523T034105_059316_075C92_rtc gates removed: 3 feature | S1A 03:40 | ≥168 | 14.7 banded | -15.2 (untrusted) |
2025-05-17provenanceS1C_IW_GRDH_1SDV_20250517T033921_20250517T033946_002365_rtc · S1C_IW_GRDH_1SDV_20250517T033946_20250517T034011_002365_rtc gates removed: 5 feature | S1C 03:39 | 142 | 0.9 | -17.4 |
2025-05-11provenanceS1A_IW_GRDH_1SDV_20250511T034041_20250511T034106_059141_075681_rtc | S1A 03:40 | ≥158 | 13.2 banded | -17.9 (untrusted) |
2025-05-05provenanceS1C_IW_GRDH_1SDV_20250505T033920_20250505T033945_002190_rtc · S1C_IW_GRDH_1SDV_20250505T033945_20250505T034010_002190_rtc gates removed: 6 feature | S1C 03:39 | 195 | 2.8 | -22.0 |
2025-04-29provenanceS1A_IW_GRDH_1SDV_20250429T034041_20250429T034106_058966_rtc gates removed: 2 feature | S1A 03:40 | ≥120 | 13.6 banded | -14.3 (untrusted) |
2025-04-23provenanceS1C_IW_GRDH_1SDV_20250423T033919_20250423T033944_002015_rtc · S1C_IW_GRDH_1SDV_20250423T033944_20250423T034009_002015_rtc gates removed: 4 feature | S1C 03:39 | 168 | 3.4 | -22.3 |
2025-04-17provenanceS1A_IW_GRDH_1SDV_20250417T034041_20250417T034106_058791_0748B2_rtc gates removed: 3 feature | S1A 03:40 | ≥153 | 26.5 banded | -18.1 (untrusted) |
2025-04-11provenanceS1C_IW_GRDH_1SDV_20250411T033919_20250411T033944_001840_rtc · S1C_IW_GRDH_1SDV_20250411T033944_20250411T034009_001840_rtc gates removed: 1 feature | S1C 03:39 | ≥125 | 14.3 banded | -16.2 (untrusted) |
2025-04-05provenanceS1A_IW_GRDH_1SDV_20250405T034041_20250405T034106_058616_07418C_rtc gates removed: 2 feature | S1A 03:40 | ≥137 | 11.6 banded | -18.3 (untrusted) |
2025-03-30provenanceS1C_IW_GRDH_1SDV_20250330T033919_20250330T033944_001665_rtc · S1C_IW_GRDH_1SDV_20250330T033944_20250330T034009_001665_rtc gates removed: 6 feature | S1C 03:39 | 190 | 1.1 | -20.9 |
2025-03-24provenanceS1A_IW_GRDH_1SDV_20250324T034041_20250324T034106_058441_073A74_rtc gates removed: 2 feature | S1A 03:40 | ≥181 | 14.6 banded | -15.1 (untrusted) |
2025-03-12provenanceS1A_IW_GRDH_1SDV_20250312T034040_20250312T034105_058266_07338A_rtc gates removed: 3 feature | S1A 03:40 | ≥135 | 22.0 banded | -17.8 (untrusted) |
2025-02-28provenanceS1A_IW_GRDH_1SDV_20250228T034040_20250228T034105_058091_072C73_rtc gates removed: 2 feature | S1A 03:40 | ≥211 | 19.6 banded | -19.1 (untrusted) |
2025-02-16provenanceS1A_IW_GRDH_1SDV_20250216T034040_20250216T034105_057916_072551_rtc gates removed: 3 feature | S1A 03:40 | ≥204 | 17.8 banded | -16.3 (untrusted) |
2025-02-04provenanceS1A_IW_GRDH_1SDV_20250204T034041_20250204T034106_057741_071E47_rtc gates removed: 4 feature | S1A 03:40 | 131 | 0.7 | -15.5 |
2025-01-23provenanceS1A_IW_GRDH_1SDV_20250123T034041_20250123T034106_057566_07175D_rtc gates removed: 6 feature | S1A 03:40 | 187 | 0.8 | -20.0 |
2025-01-11provenanceS1A_IW_GRDH_1SDV_20250111T034042_20250111T034107_057391_07106A_rtc gates removed: 6 feature | S1A 03:40 | ≥240 | 10.5 banded | -20.8 (untrusted) |
“machine” = automated count, not verified image by image. One row per satellite pass; the survey above summarizes these.
Change — latest observation
| reference | date | |
|---|---|---|
| previous pass | — | not computable — the latest pass is banded, so its count is a floor and no change can be read from it |
| ~1 week | — | not computable — the latest pass is banded, so its count is a floor and no change can be read from it |
| ~1 month | — | not computable — the latest pass is banded, so its count is a floor and no change can be read from it |
| ~1 year | — | not computable — the latest pass is banded, so its count is a floor and no change can be read from it |
Reference selection is mechanical: nearest earlier observation to (latest − 7 / 30 / 365 days), within ±2 / ±7 / ±15 days; no observation in tolerance renders as “—”. Changes are shown against named dates only — never against an average.
Pass calendar
● censused pass ○ pass exists, not yet censused (no mark = no pass: the satellite was not overhead).
2025
01-11 ●01-23 ●02-04 ●02-16 ●02-28 ●03-12 ●03-24 ●03-30 ●04-05 ●04-11 ●04-17 ●04-23 ●04-29 ●05-05 ●05-11 ●05-17 ●05-23 ●05-29 ●06-04 ●06-10 ●06-16 ●06-22 ●06-28 ●07-04 ●07-10 ●07-16 ●07-22 ●07-28 ●08-03 ●08-09 ●08-15 ●08-21 ●08-27 ●09-02 ●09-08 ●09-14 ●09-20 ●09-26 ●10-02 ●10-08 ●10-14 ●10-20 ●10-26 ●11-01 ●11-07 ●11-13 ●11-19 ●11-25 ●12-01 ●12-07 ●12-13 ●12-19 ●12-25 ●12-31 ●
2026
01-06 ●01-12 ●01-18 ●01-24 ●01-30 ●02-05 ●02-11 ●02-17 ●03-01 ●03-07 ●03-13 ●03-19 ●03-25 ●03-31 ●04-06 ●04-12 ●04-18 ●04-24 ●04-30 ●05-06 ●05-13 ●05-18 ●05-24 ●05-25 ●05-30 ●06-11 ●06-18 ●06-23 ●06-30 ●07-06 ●07-12 ●07-18 ●07-24 ●07-30 ●08-05 ●
Revisions — shown, never silent
2026-07-31 — F2 re-census (curator-ratified 2026-07-31): the census walkers lost ownership of a ~1.28 km southern band on every date (Trap 10; fixed via tile_walk, commit da2334c). The 87-date diff-run measured 126 recovered detections (27 at >=100 m across 22 dates, five >=150 m) plus 2-3 seam-truncated hulls (one 82.6 m 'small craft' actually 143.4 m). Closure-tail dates unchanged (no >=100 m gain after 2026-05-25). Fixed censuses promoted from the diff-run; whole corpus re-gated and re-recorded; band_score_db carried forward by the write_record COALESCE guard. The blind-draw calibration predates the recovered strip (~1.4% of the box) — recorded on the graduation note.. 81 count(s) across 56 row(s) changed. Method effect, not a world event.
2025-01-11: vessels 413 → 414; 2025-01-23: vessels 334 → 341; 2025-02-04: ≥100 m 130 → 131, vessels 215 → 219; 2025-02-28: vessels 286 → 287; 2025-03-12: vessels 220 → 223; 2025-04-11: vessels 209 → 211; 2025-04-17: ≥100 m 152 → 153, vessels 232 → 234; 2025-05-05: ≥100 m 193 → 195, vessels 424 → 428; 2025-05-17: vessels 192 → 194; 2025-05-29: vessels 186 → 189; 2025-06-28: ≥100 m 124 → 125, vessels 279 → 283; 2025-07-10: vessels 242 → 246; 2025-07-16: vessels 228 → 229; 2025-07-22: ≥150 m 19 → 20, ≥100 m 142 → 146, vessels 289 → 297; 2025-07-28: vessels 261 → 262; 2025-08-03: ≥100 m 236 → 237, vessels 334 → 337; 2025-08-15: ≥100 m 259 → 260, vessels 402 → 403; 2025-08-21: ≥100 m 187 → 188, vessels 294 → 295; 2025-08-27: vessels 362 → 364; 2025-09-02: ≥150 m 29 → 30, ≥100 m 175 → 176, vessels 273 → 274; 2025-09-08: vessels 270 → 271; 2025-09-14: vessels 267 → 268; 2025-09-20: vessels 355 → 357; 2025-09-26: vessels 340 → 342; 2025-10-02: ≥100 m 236 → 237, vessels 388 → 391; 2025-10-08: vessels 296 → 297; 2025-10-14: vessels 443 → 446; 2025-10-26: ≥100 m 198 → 199, vessels 307 → 308; 2025-11-01: vessels 377 → 381; 2025-11-07: ≥150 m 30 → 31, ≥100 m 222 → 223, vessels 313 → 315; 2025-11-13: ≥100 m 267 → 268, vessels 379 → 381; 2025-11-19: vessels 333 → 334; 2025-12-13: vessels 292 → 295; 2025-12-19: ≥100 m 289 → 290; 2025-12-25: vessels 376 → 377; 2025-12-31: vessels 327 → 328; 2026-01-06: vessels 342 → 343; 2026-01-12: vessels 345 → 346; 2026-01-18: vessels 244 → 246; 2026-01-24: vessels 300 → 302; 2026-01-30: ≥100 m 243 → 244, vessels 314 → 315; 2026-03-07: ≥100 m 215 → 216, vessels 365 → 368; 2026-03-13: ≥100 m 162 → 163, vessels 231 → 232; 2026-03-25: ≥150 m 29 → 30, ≥100 m 156 → 158, vessels 274 → 281; 2026-03-31: vessels 242 → 243; 2026-04-12: ≥100 m 132 → 133, vessels 217 → 219; 2026-04-24: vessels 214 → 216; 2026-05-06: vessels 433 → 437; 2026-05-13: vessels 236 → 239; 2026-05-18: ≥150 m 25 → 26, ≥100 m 215 → 216, vessels 386 → 387; 2026-05-24: vessels 211 → 214; 2026-05-25: ≥100 m 172 → 173, vessels 252 → 253; 2026-05-30: vessels 195 → 197; 2026-06-11: vessels 245 → 246; 2026-06-30: vessels 241 → 242; 2026-07-24: vessels 37 → 38
Error notes — measured, about the instrument
- Every count on this page is a machine count. Image review happens continuously behind the instrument, but its product is the measured error rates — never a corrected number in the table. At the single-detection level a machine count can be wrong in ways only the class-level rates capture.
- Radar interference bands both raise the noise floor and null real returns; banded rows are flagged by their own band column and read as floors — a band can hide a ship, never invent one.
- Sea state changes what the radar can see: calm water lets faint, wisp-like returns surface while rough water carries only bright hulls — and on banded dates the sea-state reading itself is untrusted.
Presentation floor for this instrument: ≥100 m.