Falcon 9 launches Sentinel-6 Michael Freilich to orbit   | Photo Credit: Twitter/@SpaceX

(Subscribe to Science For All, our weekly newsletter, where we aim to take the jargon out of science and put the fun in. Click here.)

A U.S.-European satellite designed to extend a decades-long measurement of global sea surface heights was launched into Earth orbit from California on Saturday.

A SpaceX Falcon 9 rocket carrying the satellite blasted off from Vandenberg Air Force Base at 9-17 a.m. and arced southward over the Pacific Ocean. The Falcon’s first stage flew back to the launch site and landed for reuse.

The Sentinel-6 Michael Freilich satellite was released from the second stage about an hour later. It then deployed its solar panels and made first contact with controllers.

Named for a former NASA official who had a key role in developing space-based oceanography, the satellite’s main instrument is an extremely accurate radar altimeter that will bounce energy off the sea surface as it sweeps over Earth’s oceans.

Liftoff! pic.twitter.com/wnkvwe09Lb

An identical twin, Sentinel-6B, will be launched in 2025 to ensure continuity of the record.

Space-based sea level measurements have been uninterrupted since the 1992 launch of the U.S.-French satellite TOPEX-Poseidon, which was followed by a series of satellites including the current Jason-3.

Sea surface heights are affected by heating and cooling of water, allowing scientist to use the altimeter data to detect such weather-influencing conditions as the warm El Nino and the cool La Nina.

The measurements are also important for understanding overall sea level rise due to global warming that scientists warn is a risk to the world’s coastlines and billions of people.

“Our Earth is a system of intricately connected dynamics between land, ocean, ice, atmosphere and also of course our human communities, and that system is changing,” Karen St. Germain, NASA’s Earth Science Division director, said in a pre-launch briefing Friday. “Because 70% of the Earth’s surface is ocean, the oceans play an enormous role in how the whole system changes,” she said.

The new satellite is expected to have unprecedented accuracy. “This is an extremely important parameter for climate monitoring,” Josef Aschbacher, the European Space Agency’s director of Earth observation, told this week. “We know that sea level is rising...The big question is, by how much, how quickly.”

Other instruments on board will measure how radio signals pass through the atmosphere, providing data on atmospheric temperature and humidity that can help improve global weather forecasts. Europe and the United States are sharing the $1.1 billion (900 million euro) cost of the mission, which includes the twin satellite.

You have reached your limit for free articles this month.

To get full access, please subscribe.

Already have an account ? Sign in

Start your 14 days free trial. Sign Up

Dear reader,

We have been keeping you up-to-date with information on the developments in India and the world that have a bearing on our health and wellbeing, our lives and livelihoods, during these difficult times. To enable wide dissemination of news that is in public interest, we have increased the number of articles that can be read free, and extended free trial periods. However, we have a request for those who can afford to subscribe: please do. As we fight disinformation and misinformation, and keep apace with the happenings, we need to commit greater resources to news gathering operations. We promise to deliver quality journalism that stays away from vested interest and political propaganda.

Dear subscriber,

Thank you!

Your support for our journalism is invaluable. It’s a support for truth and fairness in journalism. It has helped us keep apace with events and happenings.

The Hindu has always stood for journalism that is in the public interest. At this difficult time, it becomes even more important that we have access to information that has a bearing on our health and well-being, our lives, and livelihoods. As a subscriber, you are not only a beneficiary of our work but also its enabler.

We also reiterate here the promise that our team of reporters, copy editors, fact-checkers, designers, and photographers will deliver quality journalism that stays away from vested interest and political propaganda.

Suresh Nambath

Please enter a valid email address.

“We want countries to aim for 90% of girls under 15 vaccinated, 70% of eligible women identified and treated, 90% of women with invasive cancer treated,” Dr. Princess Nothemba Simelela from South Africa, WHO assistant director general, told a news briefing.

Subscribe to The Hindu now and get unlimited access.

Already have an account? Sign In

Start your 14 days free trial Sign Up