Thursday, 22 November, 2018

NASA’s Dawn Spacecraft Has Powered Down for Good

NASA's Dawn Asteroid Mission Ends as Fuel Runs Out NASA's 'Dawn Mission' to an asteroid belt comes to an end
Sandy Nunez | 05 November, 2018, 22:36

The U.S. space agency NASA declared on Thursday that its spacecraft Dawn has run out of fuel and gone silent, marking the end of its historic mission to study the two most massive bodies in the asteroid belt.

In 2011, it arrived at Vesta, the second largest object in the asteroid belt that is nearly twice the size of California.

Dawn's demise is the latest in a series of spacecraft troubles for NASA.

Launched in 2007, Dawn accomplished a journey propelled by ion engines that put about 4.3 billion miles (6.9 billion km) on its odometer. Now that it's no longer capable of communicating, much less maneuvering, it is expected to remain in orbit around Ceres for decades or longer.

On Tuesday, Nasa announced that its exoplanet-hunting Kepler Space Telescope had run out of hydrazine fuel, and the craft would be commanded to cease operations. Before joining Sun Star Times Andy has written for NPR, Motherboard, MSN and the Huffington Post.

The space agency also says Dawn's observations, of the two large asteroid belt objects, support a concept that dwarf planets could have held oceans over a substantial part of their history - and perhaps still do.

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The spacecraft itself may indeed be dead, but Dawn's contribution to science is far from over.

Thomas Zurbuchen, the associate administrator of NASA's Directorate of Scientific Missions, in Washington, praised Dawn's "science life" and "incredible technical achievements". Among its accomplishments, Dawn showed how important location was to the way objects in the early solar system formed and evolved.

"In many ways, Dawn's legacy is just beginning", said Dawn's principal investigator Carol Raymond. In addition to returning a carbon-rich asteroid sample and studying Bennu's surface and composition, NASA's OSIRIS-REx will also look into how sunlight affects its orbit and document its regolith, the layer of material covering its surface.

Dawn produced a complete map of the surface of Ceres and discovered ice volcanoes. The craft will continue to orbit Ceres for at least 20 years, though many on the team put that number closer to 50.

So, while the mission plan doesn't provide the closure of a final, fiery plunge - the way NASA's Cassini spacecraft ended previous year, for example - at least this is certain: Dawn spent every last drop of hydrazine making science observations of Ceres and radioing them back so we could learn more about the solar system we call home.