Friday, 18 January, 2019

NASA’s Dawn mission to asteroid belt ends

Another NASA spacecraft runs out of steam, 2nd this week NASA asteroid-exploring Dawn spacecraft says a sad goodbye
Sandy Nunez | 04 November, 2018, 21:54

According to the space agency, Dawn was supposed to communicate with its team on October 31 and again today, but neither session took place. Arrays of the data collected by Dawn will be deeply researched by scientists who are trying to figure out how planets grow and geologically differenciate when and where life may have formed in the Solar system. But there is no solution for a lack of fuel, and though the spacecraft would have shut down its systems and run off battery power, that battery can not be recharged if the craft is unable to orient its solar panels toward the Sun.

The spacecraft had been on its way out since June, NASA engineers sending it into its closest orbit with dwarf planet Ceres on the last few months of its fuel.

In its 11 years, Dawn has traveled a total of 4.3 billion miles (6.9 billion kilometers) and accomplished a long list of firsts. In 2011, he achieved the largest asteroid Solar system asteroid Vesta, and explored it until August 2012, then went to the dwarf planet Ceres and went on its orbit in March 2015, where it remains still.

Nasa's Dawn spacecraft heads toward the dwarf planet Ceres as seen in this undated artist's conception released January 22, 2014.

"The demands we put on Dawn were tremendous, but it met the challenge every time", Rayman said in the statement. "It's hard to say goodbye to this incredible spaceship, but it's time", said Mission Director and Chief Engineer Marc Rayman at NASA's Jet Propulsion Laboratory (JPL). "It's hard to say goodbye to this wonderful spaceship, but it's time".

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It's been a sad week for NASA missions. Both spacecraft ended their missions because they ran out of hydrazine fuel needed for attitude control, and both had suffered failures of reaction control wheels earlier in their missions that made them rely on their thrusters more than originally planned.

Among its accomplishments, Dawn showed how important location was to the way objects in the early solar system formed and evolved, NASA said. Dawn also reinforced the idea that dwarf planets could have hosted oceans over a significant part of their history - and potentially still do.

"In many ways, the study of the legacy of Dawn has just begun". They mapped Vesta and Ceres from orbit instead of using telescopes or flybys for more in-depth data.

Because Ceres has conditions of interest to scientists who study chemistry that leads to the development of life, NASA follows strict planetary protection protocols for the disposal of the Dawn spacecraft.

Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate, paid tribute to a mission that narrowly dodged cancellation during the run-up to its launch in 2007. Particularly with the discovery of 'Oumuamua, a comet from another solar system, Dawn's data on Ceres and Vesta will help scientists rewind the clock to better understand how planetary systems - our own and others - form. Northrop Grumman in Dulles, Virginia, designed and built the spacecraft.