CaliToday (17/11/2025): The Sentinel-6B satellite, launching from California, will provide unprecedented data to monitor global sea-level rise and improve weather forecasting.
VANDENBERG SPACE FORCE BASE, CALIFORNIA — In a landmark launch for climate science, SpaceX successfully lofted a vital international satellite into orbit late this evening, November 17, 2025. The mission, a joint effort between NASA and the European Space Agency (ESA), will provide the most precise data ever recorded on our planet's rising oceans.
A Falcon 9 rocket, piercing the clear California sky, carried the Sentinel-6B satellite into its designated polar orbit. The launch marks the successful continuation of a decades-long program to track sea-level rise, an escalating consequence of global climate change.
This mission is considered one of the most critical environmental launches of the decade. Here’s why it matters:
A High-Stakes Mission
The Sentinel-6B satellite is not just a single instrument; it's a sophisticated observatory designed to continue an unbroken 30-year record of ocean height measurements. Its primary goal is to provide a clear, unambiguous answer to the question: How fast are our oceans rising?
As global temperatures increase, glaciers and ice sheets melt, pouring trillions of tons of water into the sea. Simultaneously, the oceans absorb excess heat, causing the water itself to expand (a process called thermal expansion).
"We are not just measuring the ocean; we are measuring the definitive impact of a warming planet," said Dr. Karen St. Germain, Director of NASA's Earth Science Division, in a pre-launch briefing. "This data is not abstract. It is essential for protecting the hundreds of millions of people living in coastal communities around the world."
The Technology Onboard
At the heart of the Sentinel-6B is a new-generation radar altimeter. This instrument works by bouncing tiny radar pulses off the ocean's surface and precisely measuring the time it takes for the signal to return.
By doing this, the satellite can measure the ocean's surface height with astonishing millimeter-level precision from over 800 miles (1,300 km) above the Earth.
Beyond tracking sea level, the data from Sentinel-6B will also:
Improve Hurricane Forecasts: By measuring the height and temperature of the ocean surface, the satellite can identify large pools of warm water that fuel and intensify hurricanes.
Enhance Weather Models: The data will be fed into global weather models, improving the accuracy of both short-term forecasts and long-term climate projections.
Aid Ship Navigation: Real-time data on ocean currents and wave heights will help make maritime routes safer and more efficient.
A Continued Partnership
The launch of Sentinel-6B follows its twin, Sentinel-6A (also known as Michael Freilich), which has been in orbit since 2020. Having two identical satellites in orbit allows for more frequent and comprehensive coverage of the globe.
Tonight's flawless launch by SpaceX, which included the successful recovery of the Falcon 9's first-stage booster on a droneship in the Pacific, underscores the critical role of commercial partnerships in advancing public science.
With the satellite now safely deployed, controllers will spend the next few months commissioning its instruments. Once fully operational, Sentinel-6B will take over as the primary reference satellite for sea-level measurements, continuing a vital mission to watch over our planet's most critical resource.