Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Vessel
Neptune Island
MMSI 477732300
Not yet on Master's MateFlag
HKGLength
184 m
IMO
9544140
AIS reports
2
A Hong Kong craft, Neptune Island measures 184 metres. Find her under MMSI 477732300, IMO 9544140. Bring Neptune Island aboard the Master's Mate Safety Initiative Network — free, and every captain on it has the others' backs.
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Is Neptune Island your boat?
Your free claim unlocks the most powerful cruising platform ever built — anchor watch, worldwide charts, live AIS, weather routing, and a network of cruisers watching each other’s backs.
Claim this boat — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Live AIS position · Jun 10, 2026 00:13 UTC
Position
37.7693° N, 122.6675° W
Status
Under way (engine)
Speed
8.9 kn
Course
259°
Destination
CACRO
ETA
06-12 17:00 UTC
Crossing San Francisco Bay? You're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
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The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Neptune Island on the map. It hands you the full bridge:
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim Neptune Island and switch it all on
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About Neptune Island
What kind of vessel is Neptune Island?
Neptune Island is a vessel flagged to Hong Kong S.A.R..
Where was Neptune Island last seen?
Neptune Island was last reported in San Francisco Bay on public AIS.
What is Neptune Island's MMSI?
Neptune Island's MMSI is 477732300. IMO 9544140.
How big is Neptune Island?
Neptune Island is about 184 m long.
Is Neptune Island on the Master's Mate Safety Initiative Network?
Not yet. If Neptune Island is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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