NASA’s Dawn space probe, our visitor to the Solar System’s protoplanets Vesta and Ceres, is cold and dead.
The spacecraft finally ran out of fuel whilst it was orbiting Ceres, the largest object in the asteroid belt. NASA engineers noticed that it had missed two opportunities to check in with ground control on 31 October and 1 November.
The flight team investigating the breakdown have deduced that Dawn’s hydrazine fuel reserves are empty, after eliminating other possibilities for the probe's silence. Without a drop of fuel left, Dawn has no power to direct its antennas toward Earth to communicate and cannot swivel its solar panels around to take in sunlight.
Scientists have been expecting the end of Dawn for quite some time. Its 12-gallon hydrazine tank was drained down to 1.8 gallons in May, earlier this year, after the probe had traveled 6.4 billion miles (10.3 billion kilometers). NASA predicted the mission would probably last until September, but Dawn managed to cling on until the end of October.
“Today, we celebrate the end of our Dawn mission – its incredible technical achievements, the vital science it gave us, and the entire team who enabled the spacecraft to make these discoveries,” said Thomas Zurbuchen, NASA’s associate administrator for the Science Mission Directorate, on Thursday.
“The astounding images and data that Dawn collected from Vesta and Ceres are critical to understanding the history and evolution of our solar system.”
The protoplanets in the asteroid belt are ancient specimens leftover from the disk of gas and dust that formed around the Sun 4.6 billion years ago. Dawn was sent to glean new clues on how our Solar System and life on Earth formed from this ancient rubble. It began its journey to space 11 years ago in 2007, heading for the asteroid belt wedged in between Mars and Jupiter to find Vesta and Ceres.
Dawn spacecraft to get up-close and personal with dwarf planet CeresREAD MORE
The probe found surface features on Vesta and Ceres. Both were marked with craters, some iof which contained pockets of organic matter. Ceres has a volcano made entirely from ice, hinting that liquid water exist internally. Vesta also had signs of water, after researchers found evidence of ground ice on its rocks.
Now that Dawn is out of action, it will be left to silently float around Ceres. It will stay there for at least 20 years, and there’s a high probability that it’ll stay in space for 50 years.
"The fact that my car's license plate frame proclaims, 'My other vehicle is in the main asteroid belt,' shows how much pride I take in Dawn," said Marc Rayman, mission director and chief engineer at NASA's Jet Propulsion Laboratory.
"The demands we put on Dawn were tremendous, but it met the challenge every time. It's hard to say goodbye to this amazing spaceship, but it’s time."
It’s been a particularly sad week for space exploration, as NASA also laid its Kepler spacecraft to rest earlier this week. Sadly, the spacecraft also ran out of fuel too. ®