First of ESA's twin sea-level monitoring satellite Sentinel-6 is now operational

The sea-level monitoring satellite Sentinel-6 by the European Space Agency (ESA) has gone live. The Copernicus Sentinel-6 Michael Freilich, which was launched on 21 November 2020, has now become operational, according to the European Space Agency (ESA). The data generated by the satellite can now be used for ocean-weather forecasts and can help climate researchers and other data users. Several agencies collaborated to make this satellite possible including ESA, Eumetsat, National Aeronautics and Space Administration (NASA), National Oceanic and Atmospheric Administration (NOAA), and French space agency CNES (Centre National d’études Spatiales). [caption id=“attachment_9100911” align=“alignnone” width=“1280”] The Sentinel-6 Michael Freilich satellite launched from Vandenberg Air Force Base in central California on Nov. 21. NASA’s Eyes visualization tools lets you track the spacecraft as begins its mission to measure sea level height as it orbits Earth.
Credits: NASA/JPL-Caltech[/caption] Speaking about the mission, the ocean altimetry programme manager at Eumetsat, Julia Figa Saldana, said that for the past six months, they have been flying the satellite in the same orbit as Jason-3, the current altimetry reference mission. This has been done so that both the satellites get the same ‘view’ of the ocean. The data has been cross-collaborated by experts from around the world for accuracy. Currently, it is being processed at Eumetsat Germany’s Darmstadt. From this centre, the data is then provided to weather and ocean forecasting users. The satellite has a radar altimeter whose function is to measure the time taken by the radar pulses to travel to the surface of the Earth and then back again. Craig Donlon, the Sentinel-6 mission scientist at ESA said that the CDN1 transponder, which shows measurements from Sentinel-6 and Jason-3, have an absolute difference of less than 2 mm. He said that it is “remarkable for two independent satellites operating at an altitude of 1330 km”.

About the Sentinel-6 satellites

While Sentinel-6 is the first satellite of the mission, its identical website Sentinel-6B will be launched five years later in 2025. It is expected to provide data till at least 2030. They are designed to last for five-and-a-half years but could provide data for far longer. The **Sentinel satellites** are each about the size and shape of a large minivan topped with slanted solar panels and weigh nearly 1,200 kilos, including rocket fuel. The satellites will circle the planet in the same orbit as earlier missions that supplied sea-surface height data over the last three decades, mapping 95 percent of Earth’s ice-free ocean every ten days. They will continue to provide data as accelerating sea-level rise is arguably the climate change impact that will affect the largest number of people over the next three decades. Nearly 800 million people live within five metres of sea level, and even an increase in sea level of a few centimetres can translate into vastly more damage from high tides and storm surges. Sea-surface heights are affected by heating and cooling of water, allowing scientist to use the altimeter data to detect such weather-influencing conditions as the warm El Nino and the cool La Nina. Previously, it was reported that the cost of the mission, which is around USD 1.1 billion or 900 million euros, has been shared by ESA and NASA.