European Spaceflight and SpaceWatch reported that OHB secured a €554 million European Space Agency (ESA) contract to develop Sentinel-3 Next Generation Topography (NGT) for the European Union’s Copernicus program. The announcement was dated November 4, 2026. NGT is planned as a radar-altimetry mission, focused on measuring Earth’s surface topography.

What the contract covers

European Spaceflight describes the contract as covering the first NGT spacecraft, with an option for a second. SpaceWatch describes the mission as comprising two identical satellites. Both accounts report the €554 million development award.

European Spaceflight also reports that OHB conducted preliminary design studies for NGT in 2022 and for the separate Sentinel-3 Next Generation Optical (NGO) mission in 2024. ESA awarded parallel study contracts to Airbus Defence and Space for NGT and Thales Alenia Space for NGO. OHB project manager Ann-Theres Schulz described intended improvements in height-measurement accuracy, area coverage and revisit rates.

What NGT and NGO are designed to observe

A computer-generated satellite with a long solar array appears above Earth against a dark star field.

The planned missions divide their observation work by method: NGT focuses on radar altimetry, while NGO is designed for observations in visible and infrared wavelengths and for measuring surface temperatures.

MissionPlanned focusObservations
Sentinel-3 NGTRadar altimetryEarth’s surface topography
Sentinel-3 NGOOptical and infrared observationVisible and infrared observations; surface temperatures
NGT and NGO are planned as complementary observation missions: one focuses on radar altimetry, the other on visible and infrared observations and surface temperature.

Sentinel-3’s earlier mission heritage

In its 2016 introduction to Sentinel-3A, ESA names ERS, Envisat and Cryosat as part of the Sentinel-3 mission’s scientific heritage. That history predates the NGT development contract.

Tentative launch years

European Spaceflight reported that an International Laser Ranging Service overview published in July 2026 tentatively listed 2033 and 2035 as NGT launch years.