The two satellites make up the Copernicus Sentinel-6/Jason-CS (Continuity of Service) mission, the latest in a series of ocean-observing radar altimetry missions that have monitored Earth’s changing seas since the early 1990s.

As with its predecessor, Sentinel-6B satellite also will provide key information about wind speeds, wave heights, atmospheric temperature, and humidity. Moreover, because water expands as its temperature increases, researchers can tell which parts of the ocean are warmer than others based on where the sea surface height is greater.

Combined with data from other instruments, that knowledge can help in forecasting marine weather, including the development of hurricanes, which intensify with warmer water. Also, because large currents are taller than surrounding waters due to their higher temperatures, sea surface measurements can shed light on interactions between the Gulf Stream, for example, and nearby waves. Where they meet, seas can become rougher, presenting a hazard to even the largest ships.

“Sentinel-6B is a testament to the value of NASA’s partnership missions to put actionable satellite information and science into the hands of decision-makers on the ground,” said Karen St. Germain, director, NASA Earth Science Division at the agency’s headquarters. “Sentinel-6B will collect ocean surface observations that will inform decisions critical to coastal communities, commercial shipping and fishing, national defense, and emergency preparedness and response. This is what NASA does —puts advanced technology and science into action for the benefit of the nation.”

When Sentinel-6B reaches its operating elevation, the satellite will fly about 30 seconds behind Sentinel-6 Michael Freilich, which carries identical science instruments. Once the mission finishes cross-calibrating the data collected by the two, Sentinel-6 Michael Freilich will move into a different orbit, and Sentinel-6B will take over the role of official reference satellite, orbiting Earth about 13 times a day at 830 miles (1,336 kilometers) above the surface.

“Sentinel-6B demonstrates the versatile Earth science applications made possible by expertly engineered, space-based technology. The satellite’s powerful suite of instruments will measure about 90% of Earth’s oceans down to fractions of an inch — continuing to add to a vital dataset that America and a growing global community depend on,” said Dave Gallagher, director, NASA’s Jet Propulsion Laboratory (JPL) in Southern California.

More about Sentinel-6B

Copernicus Sentinel-6/Jason-CS is a collaboration between ESA, the European Union, EUMETSAT, NASA, and NOAA. French space agency CNES (Centre National d’Études Spatiales) contributed technical support. Copernicus, which includes the Sentinel missions, is the European Union’s Earth observation program led by the European Commission.

A division of Caltech in Pasadena, JPL contributed three science instruments for each Sentinel-6 satellite: the Advanced Microwave Radiometer, the Global Navigation Satellite System – Radio Occultation, and the laser retroreflector array. NASA also is contributing launch services, ground systems supporting operation of the NASA science instruments, the science data processors for two of these instruments, and support for the U.S. members of the international Ocean Surface Topography Science Team, and Sentinel-6 science teams.

To learn more about Sentinel-6B, visit:

https://science.nasa.gov/mission/sentinel-6B/