Launch of a satellite to map the world’s oceans, lakes and rivers

A US-French satellite that will map nearly all of the world’s oceans, lakes and rivers went into orbit on Friday.

The pre-dawn launch aboard a SpaceX rocket from Vandenberg Space Force Base in California capped a very successful year for NASA.

Dubbed SWOT – short for Surface Water and Ocean Topography – the satellite is needed more than ever because climate change worsens droughts, floods and coastal erosion, according to scientists. Cheers erupted from control centers in California and France as the spacecraft began its mission.

“This is a pivotal moment, and I’m very excited about it,” said NASA program manager Nadya Vinogradova-Shiffer. “We’re going to see Earth’s water like never before.”

The size of an SUV, the satellite will measure the height of water over more than 90% of the Earth’s surface, allowing scientists to track the flow and identify potential high-risk areas. It will also study millions of lakes as well as 1.3 million miles (2.1 million kilometers) of rivers, from source to mouth.

The satellite will beam radar pulses back to Earth, the signals bouncing back to be received by a pair of antennae, one at each end of a 33-foot (10-meter) pole.

It should be able to distinguish currents and eddies less than 13 miles (21 kilometers) in diameter, as well as areas of the ocean where masses of water of varying temperatures merge.

NASA’s current fleet of nearly 30 Earth observation satellites cannot distinguish such faint features. And while these older satellites can map the extent of lakes and rivers, their measurements aren’t as detailed, said Tamlin Pavelsky of the University of North Carolina, who is part of the mission.

Perhaps most importantly, the satellite will reveal the location and speed of sea level rise and shifting coastlines, critical to saving lives and property. It will span the globe between the Arctic and Antarctica at least once every three weeks, as it orbits over 890 kilometers above sea level. The mission is expected to last three years.

Laurie Leshin, director of NASA’s Jet Propulsion Laboratory in Pasadena, California, noted that while the agency is known for its rovers and space telescopes on Mars, “it’s the planet we care about most.”

“We have a lot of eyes on Earth,” with even more globe-surveying missions planned in the coming years, she added.

NASA and the French Space Agency collaborated on the $1.2 billion SWOT project – some 20 years in the making – with participation from Britain and Canada.

Already recycled, the first-stage thruster returned to Vandenberg eight minutes after takeoff to fly again one day. When the double sonic booms sounded, “Everyone jumped out of their skins, and it was exhilarating. What a morning,” said Taryn Tomlinson, director of earth sciences at the Canadian Space Agency.

This is the last milestone this year for NASA. Other highlights include glamorous shots of the universe from the new Webb Space Telescope; the fatal blow of the Dart spacecraft into an asteroid during the first planetary defense test; and the recent return of the Orion capsule from the moon after a test flight.


The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute Science and Education Media Group. The AP is solely responsible for all content.

Leave a Reply

Your email address will not be published. Required fields are marked *