Sentinel-3 / eo constellation
sourcingtypical 4/5 · 15 factsopticalmultispectralthermalEuropean Unionactive
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.
key details
faq
Who operates Sentinel-3?
Sentinel-3 is operated by EUMETSAT. (source, as of 2026-07-05)
How many Sentinel-3 satellites are active on orbit?
CelesTrak's catalog currently tracks 2 objects for Sentinel-3. (source, as of 2026-09-08)
When did Sentinel-3 first launch?
Sentinel-3 first launched on 2016-02-16. (source, as of 2026-07-05)
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 launched (total)2
sats active (claimed)2
sats active (verified)2
sats planned2
orbit815 km altitude
first launch2016-02-16
latest launch2018-04-25
statusactive
websiteesa.int
resolution (m)300
swath (km)unknown
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
orbit815 km altitude
sats launched (total)2
sats active (claimed)2
sats active (verified)2
sats planned2
events
timeline
- 20182018-04-25Sentinel-3B launches, joining twin Sentinel-3A in orbit (source, as of 2026-07-12)
- 20162016-02-16Sentinel-3A launches on Rockot from Plesetsk for Copernicus (source, as of 2026-07-12)
- 2016-02-09ESA signs Thales Alenia Space to a EUR450 million contract for Sentinel-3C and 3D (source, as of 2026-07-12)
- 20082008-04-14ESA signs Thales Alenia Space to a EUR305 million contract for the first Sentinel-3 (source, as of 2026-07-12)
sources
[1] en.wikipedia.org ↗
operatorwikipedia2026-07-05countrywikipedia2026-07-05sensor typeswikipedia2026-07-05sats launched (total)wikipedia2026-07-06sats active (claimed)wikipedia2026-07-06sats plannedwikipedia2026-07-05statuswikipedia2026-07-05
[2] esa.int ↗
orbitfirst-party2026-07-05first launchfirst-party2026-07-05latest launchfirst-party2026-07-05websitefirst-party2026-07-05
[4] celestrak.org ↗
sats active (verified)computed2026-09-08