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Jason-1 ocean-mapping satellite is retired after 11-plus years of surveying

French and U.S. researchers declared an 11-and-a-half-year project to survey the world’s oceans via space satellite officially over Wednesday, July 3. Jason-1, a space satellite that French and U.S. scientists had launched into space back in 2001 to track rising sea levels, was officially decommissioned following the reported failure of its last working transmitter.

It retires on a high note, though, according to NASA spokespersons, who said that Jason-1’s data transmissions made a significant contribution to efforts to forecast worldwide weather patterns and climate-change trends. Those transmissions had gone on for far longer than Jason-1’s engineers had ever expected: The satellite launched into space Dec. 7, 2001, with a mission projected to only last three to five years.

During its time in the sky, the satellite sent its research team recurring reports every 10 days of a slew of indicators of the ocean waters below, including wind speeds, sea levels, and wave height. By the time of its decommissioning this week, it has covered more than 95% of the planet’s ice-free ocean surfaces.

NASA and partner agencies employed this information to compile a 20-year record of changes in sea level brought about by climate change. That record showed an overall 1.6-inch rise in the global sea levels overall, effects of which are inevitable all across the globe, according to the researchers. The satellite also deepened the scientific community’s knowledge of the precise depths of the ocean floor, and it made possible the discovery of multiple “seamounts”—mountain formations on the ocean floor.
The satellite appeared to be close to its end last year, with its fuel depleted and some systems starting to malfunction. Nevertheless, it managed to initiate a series of observations of the Earth’s gravitational field playing out over the oceans. This late stretch of observations led to new discoveries and new series of precise measurements of our planet’s gravity.

The team finally lost contact with Jason-1 June 21 of this year, and tried unsuccessfully multiple times to reconnect. The human operators accepted the foregone conclusion and turned off the altitude controls on Monday, letting the satellite passively drift off into free orbit. Its solar-powered batteries will probably continue to run for another 90 days, and the satellite may remain in orbit around Earth for as long as another thousand years, according to NASA.

Other satellites carry on its work, though. Jason-2 monitors the ocean to this day, having been launched in 2008, and NASA plans to launch Jason-3 in 2015.

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