NASA will keep Dawn in Ceres’ orbit
NASA reneged initial plans to send the Dawn spacecraft to probe another asteroid. Dawn recently completed its mission of the dwarf planet Ceres this past Thursday, and scientists wanted to leverage the spacecraft’s remaining fuel to observe a nearby asteroid.
NASA had formerly dismissed to name the asteroid, but the team of researchers unveiled its name through a post on its website. Named 145 Adeona, the asteroid is 150-kilometers (93 miles) wide. A third proposal would have sent Dawn out of Ceres’ orbit later this month to study the Sun for a few years; it then would have been sent to 145 Adeona by May 2019.
But affiliates of NASA’s Planetary Mission Senior Review Panel felt that Dawn would be better utilized to continue its probe of Ceres.
Scientists proposed to send Dawn to asteroid 145 Adeona during a meeting with associates of the Small Bodies Assessment Group (SBAG) on June 28th. Researchers reasoned that a subsequent visit to a nearby asteroid would provide more data than just having Dawn study Ceres.
Pointing to the recently completed probe around the dwarf planet earlier, Raymond said,”I think we’ve gotten so much already that the incremental amount of knowledge that we would gain would be maybe not as great as one would have thought.”
The additional Dawn exploration was proffered, as scientists found a way to conserve the spacecraft’s fuel of hydrazine, which is used to charge its thrusters. Scientists first approached this method in 2012 while Dawn was still probing the Vesta asteroid. But Dawn experienced issues with its wheels, which would have depleted all of its hydrazine supply before exiting Ceres.
Dawn’s leftover fuel is enough to keep it in flight in Ceres’ orbit until 2017. If the setbacks with its wheels were fixed, the timeframe could be extended. Although Dawn was a disappointment, NASA greenlighting a secondary space mission.
The New Horizons spacecraft, which just finalized its mission to Pluto, will be sent to a distant object classified as 2014 MU69 in the Kuiper Belt. January 1, 2019, is the target date.