A satellite built to observe nearly all the water on our planet’s surface lifted off on its way to low-Earth orbit on December 16.
- The US space agency NASA on December 16 launched the Surface Water and Ocean Topography (SWOT) spacecraft atop a SpaceX rocket from Space Launch Complex 4E at Vandenberg Space Force Base in California.
Salient features of SWOT
- SWOT was built for NASA and the French space agency Centre National d’Études Spatiales (CNES) and also has contributions from the Canadian Space Agency (CSA) and the UK Space Agency.
- With a prime mission of three years, the SWOT satellite will measure the height of water in freshwater bodies and the ocean on more than 90% of Earth’s surface.
- This data will provide new insights into how the ocean influences climate change; how a warming world affects lakes, rivers, and reservoirs; and how communities can better prepare for disasters, such as floods.
- SWOT will cover the entire Earth’s surface between 78 degrees south and 78 degrees north latitude at least once every 21 days, sending back about one terabyte of unprocessed data per day.
- The scientific heart of the spacecraft is an innovative instrument called the Ka-band radar interferometer (KaRIn), which marks a major technological advance.
- KaRIn bounces radar pulses off the water’s surface and receives the return signal using two antennas on either side of the spacecraft.
- This arrangement – one signal, two antennas – will enable engineers to precisely determine the height of the water’s surface across two swaths at a time, each of them 30 miles.
