Vandenberg Space Force Base, United States - November 17, 2025 NASA and SpaceX have launched the U.S.–European Sentinel-6B satellite, a pickup-truck-sized spacecraft designed to extend decades of sea level measurements that support weather forecasting, coastal protection, and major commercial operations. The satellite lifted off aboard a SpaceX Falcon 9 from Launch Complex 4 East at 9:21 p.m. PST on Nov. 16. Contact with a ground station in northern Canada was confirmed at 10:54 p.m., about 90 minutes later, with all systems operating normally. “Understanding tidal patterns down to the inch is critical in protecting how we use our oceans every day on Earth,” said Nicky Fox of NASA’s Science Mission Directorate. She noted that Sentinel-6B builds on the legacy of Sentinel-6 Michael Freilich and will improve forecasts used nationwide. She added that its measurements will also support safer astronaut reentry, including crews from Artemis Moon missions. Designed to capture sea levels at local and global scales, the satellite will strengthen U.S. flood predictions that safeguard coastal infrastructure ranging from real estate to energy facilities. Sentinel-6B replaces Sentinel-6 Michael Freilich, launched in 2020, which became the official reference satellite for global sea level measurements. The mission reflects a collaboration among NASA, ESA, EUMETSAT, NOAA, and the European Union’s Copernicus program. “Collaboration between partners is key to a mission such as Sentinel-6,” said Simonetta Cheli of ESA. She called the launch a demonstration of what international agencies and industries can achieve together, enabling continued access to high-precision data needed for climate understanding and coastal protection. The two satellites form the Copernicus Sentinel-6/Jason-CS mission, the latest in a radar-altimetry line monitoring Earth’s oceans since the early 1990s. Sentinel-6B will also deliver data on wind speeds, wave heights, atmospheric temperature, and humidity. Because warmer water expands, the satellite can identify hotter regions of the ocean based on elevated sea surface height. Combined with other instruments, these observations support marine weather forecasting, including hurricane development, which accelerates over warmer water. The measurements also reveal how major currents such as the Gulf Stream interact with nearby waves, creating rough seas that challenge even large ships. “Sentinel-6B is a testament to the value of NASA’s partnership missions,” said Karen St. Germain of NASA’s Earth Science Division. She emphasized that the satellite’s ocean data will support decisions across coastal communities, shipping, fishing, national defense, and emergency response. Once it reaches its operating altitude, Sentinel-6B will fly about 30 seconds behind Sentinel-6 Michael Freilich while their data are cross-calibrated. Afterward, the older satellite will shift orbit and Sentinel-6B will assume full reference duties, circling Earth about 13 times per day at 830 miles (1,336 kilometers). “Sentinel-6B demonstrates the versatile Earth science applications made possible by expertly engineered, space-based technology,” said Dave Gallagher of NASA’s Jet Propulsion Laboratory, noting that its instruments will measure roughly 90% of Earth’s oceans down to fractions of an inch.