# Sentinel-3B
*missions*

## Specifications
- **operator**: eumetsat
- **actual launch**: 2018-04-25
- **current status**: operational
- **orbit type**: Sun-synchronous orbit, 814.5 km altitude, 98.65 deg inclination, 10:00 descending node, 27-day repeat
- **revisit days**: 1.8
- **paired revisit days**: 0.9
- **tasking supported**: false
- **current geographic priority**: Global ocean, land, ice, inland-water, and atmosphere observation
- **launch vehicle**: rockot-breeze-km
- **entity type**: mission
- **last verified date**: 2026-06-14
- **verified by**: agency-doc
- **claim status**: agency-sourced
- **provider**: eumetsat
- **attributes**: {"operator":"eumetsat","actual_launch":"2018-04-25","current_status":"operational","orbit_type":"Sun-synchronous orbit, 814.5 km altitude, 98.65 deg inclination, 10:00 descending node, 27-day repeat","revisit_days":1.8,"paired_revisit_days":0.9,"tasking_supported":false,"current_geographic_priority":"Global ocean, land, ice, inland-water, and atmosphere observation","launch_vehicle":"rockot-breeze-km"}
- **relevance**: in-scope

## Editorial
Sentinel-3B is the second flight unit of the Copernicus Sentinel-3 programme, jointly operated by ESA and EUMETSAT. It launched on 2018-04-25 into a sun-synchronous orbit at 814.5 km altitude, 98.65 degree inclination, with a 10:00 descending node and a 27-day repeat cycle. When paired with Sentinel-3A the combined revisit is approximately 0.9 days globally. The satellite carries four main instruments: the Ocean and Land Colour Instrument (OLCI) for ocean colour and terrestrial vegetation monitoring; the Sea and Land Surface Temperature Radiometer (SLSTR) for sea and land surface temperature measurements; the SAR Radar Altimeter (SRAL) for ocean topography, sea ice and inland water level; and the Microwave Radiometer (MWR) providing wet-tropospheric path delay correction for the altimeter. Precise orbit determination is supported by DORIS, a GPS receiver, and a laser retroreflector. The mission delivers global measurements for ocean colour, sea surface temperature, sea level, sea ice, coastal water quality, and inland water extent. [^sentiwiki-s3-mission][^wmo-sentinel-3b][^eumetsat-s3-altimetry-l1]

## Compositional position
- Sentinel-3B --[mission_payloads]--> olci (products)
- Sentinel-3B --[mission_payloads]--> slstr (products)
- Sentinel-3B --[mission_payloads]--> sral (products)
- Sentinel-3B --[mission_payloads]--> mwr (products)
- Sentinel-3B --[mission_payloads]--> sentinel-3-doris (products)
- Sentinel-3B --[mission_payloads]--> sentinel-3-gps (products)
- Sentinel-3B --[mission_payloads]--> sentinel-3-lrr (products)
- Sentinel-3B --[related-topic]--> coastal-water-quality (topics)
- Sentinel-3B --[related-topic]--> marine-primary-production (topics)
- Sentinel-3B --[related-topic]--> sea-surface-temperature (topics)
- Sentinel-3B --[related-topic]--> sea-level (topics)
- Sentinel-3B --[related-topic]--> sea-ice (topics)
- Sentinel-3B --[related-topic]--> inland-water (topics)

## Sources
- [sentiwiki-s3-mission] | Copernicus SentiWiki Sentinel-3 mission | https://sentiwiki.copernicus.eu/web/s3-mission | tier=agency-doc | accessed=2026-06-14
- [wmo-sentinel-3b] | WMO OSCAR satellite record: Sentinel-3B | https://space.oscar.wmo.int/satellites/view/sentinel_3b | tier=agency-doc | accessed=2026-06-14
- [eumetsat-s3-altimetry-l1] | EUMETSAT Sentinel-3 altimetry level 1 data guide | https://user.eumetsat.int/resources/user-guides/sentinel-3-altimetry-level-1-data-guide | tier=agency-doc | accessed=2026-06-14

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Source: https://eo-atlas.org/missions/sentinel-3b
Maintainer: SpectraWorks B.V. (CC-BY 4.0)