The Lord giveth, and the Lord taketh away. While scientists celebrated funding for many missions being extended recently, including NASA’s New Horizons spacecraft, others were left bemoaning their luck.
That’s because the Dawn spacecraft, currently in orbit around the dwarf planet Ceres in the asteroid belt, has been denied a proposal to leave Ceres and explore another object of interest.
Dawn, as you may know, is the first spacecraft ever to orbit two separate bodies other than Earth, having traveled to the protoplanet Vesta in 2011, and then to Ceres in 2015. But Dawn has now completed its science goals at Ceres, so the mission team had asked NASA if they could send it to a new, unchartered destination – the relatively small asteroid Adeona in the asteroid belt.
Sadly, though, NASA rejected this proposal last week, instead directing the team to remain in orbit around Ceres. The reason, NASA said, is that Ceres’ orbit will soon bring it closer to the Sun, so some interesting changes could take place on its surface.
Personally, it’s a bit of a bummer. To have a spacecraft so far from Earth, with the ability to explore different locations thanks to its ion engine, it seems like a bit of a waste. Marc Rayman, Dawn's chief engineer and mission director, told IFLScience that the new directive was still exciting – although perhaps not as much as some had hoped.
“I am very happy with this decision,” he said. “Some people on Dawn thought Ceres was the better choice, and some thought Adeona was. NASA's decision was not based on the team's preference, nor should it be. The decision was based on an objective, rational assessment of the data we provided on the two options.
“The third option was to end the mission now. That choice would have been a disappointment.”
Dawn wouldn’t have orbited Adeona, but simply flown by in May 2019 before the mission came to an end, according to Wired. Still, it would have been exciting to see this other body, which is much smaller than Ceres (950 kilometers/590 miles) and Vesta (525 kilometers/326 miles), at just 150 kilometers (93 miles) across.
Dawn’s primary mission at Ceres actually ended on June 30, so we’ll have to wait and see what the spacecraft is tasked to do next. Those hoping for a new destination, though, are out of luck.