Copernicus Sentinel-3 measures systematically Earth's oceans, land, ice and atmosphere to monitor and understand large-scale global dynamics. The mission delivers near-real-time data for ocean and weather forecasting, carrying instruments for ocean colour, sea and land surface temperature, and altimetry.
imaging modes
OLCI (Ocean and Land Colour Imager)resolution300 mswath1270 km
SLSTR nadir view (500 m VNIR/SWIR, 1 km MWIR/TIR)resolutionnot statedswath1420 km
SLSTR backward view (500 m VNIR/SWIR, 1 km MWIR/TIR)resolutionnot statedswath750 km
facts
operatorEUMETSAT
countryEuropean Union
sensor typesoptical, multispectral, thermal
sats launchedtotal3
sats activeclaimed2
sats activeverified3
sats planned2
orbit815 km altitude
first launch2016-02-16
latest launch2018-04-25
statusactive
websiteesa.int
resolutionm300
swathkmunknown
revisitless than or equal to four days (varies with latitude)
spectral bandsOLCI: 21 VNIR/SWIR bands, SLSTR: 11 bands (3 VNIR, 3 SWIR, 5 MWIR/TIR)
sats active (verified) counts objects currently tracked in CelesTrak's catalog for this constellation. It is a tracking count, not an operator claim about satellite health.
orbit
sats launchedtotal3
sats activeclaimed2
sats activeverified3
sats planned2
orbit815 km altitude
crawled events
timeline
- 20182018-04-25Sentinel-3B launches, joining twin Sentinel-3A in orbitas of 2026-07-12
- 20162016-02-16Sentinel-3A launches on Rockot from Plesetsk for Copernicusas of 2026-07-12
- 2016-02-09ESA signs Thales Alenia Space to a EUR450 million contract for Sentinel-3C and 3Das of 2026-07-12
- 20082008-04-14ESA signs Thales Alenia Space to a EUR305 million contract for the first Sentinel-3as of 2026-07-12
sources
[1] en.wikipedia.org ↗
operatorwikipedia2026-07-05countrywikipedia2026-07-05sensor typeswikipedia2026-07-05sats active (claimed)wikipedia2026-07-06sats plannedwikipedia2026-07-05statuswikipedia2026-07-05
[2] esa.int ↗
sats launched (total)first-party2026-09-17orbitfirst-party2026-07-05first launchfirst-party2026-07-05latest launchfirst-party2026-07-05websitefirst-party2026-07-05
[4] celestrak.org ↗
sats active (verified)computed2026-11-06
faq
Who operates Sentinel-3?
Sentinel-3 is operated by EUMETSAT. as of 2026-07-05
How many Sentinel-3 satellites are active on orbit?
CelesTrak's catalog currently tracks 3 objects for Sentinel-3. as of 2026-11-06
When did Sentinel-3 first launch?
Sentinel-3 first launched on 2016-02-16. as of 2026-07-05