The Sentinel-6 Michael Freilich (S6MF) or Sentinel-6A is a radar altimeter satellite developed in partnership between several European and American organizations.

S6MF includes synthetic-aperture radar altimetry techniques to improve ocean topography measurements, in addition to rivers and lakes.

[5][6] Formerly called Sentinel-6A and Jason-CS A (Jason Continuity of Service-A), it was renamed in honor of the former director of NASA Earth Science Division, Michael Freilich, who was instrumental in advancing space-based ocean measurements.

[7] Since the launch of TOPEX/Poseidon on 10 August 1992, high-precision satellite altimeters have been essential to monitor how the ocean stores and redistributes heat, water, and carbon in the climate system.

The two satellites, Sentinel-6 Michael Freilich and Sentinel-6B, will extend this legacy through to at least 2030, which will provide a nearly forty-year record of sea level rise as well as changes in ocean currents.