Dawn's operations in cruise from Vesta to Ceres

作者：Rayman Marc D^*; Mase Robert A

来源：Acta Astronautica, 2014, 103: 113-118.

DOI：10.1016/j.actaastro.2014.06.042

• Dawn
• Vesta
• Ceres
• Asteroid
• Ion propulsion
• Solar electric propulsion

On 5 September 2012, Dawn concluded its successful exploration of Vesta, the second most massive object in the main asteroid belt. The spacecraft departed after 14 months in orbit and is now using its ion propulsion system to travel to dwarf planet Ceres, the most massive main-belt asteroid. The principal activity now is thrusting with the ion propulsion system to provide the 3.5 km/s required to rendezvous with Ceres early in 2015. Because two of the four reaction wheels have experienced faults and are likely unrecoverable, a substantial effort has been invested in preparing for Ceres operations with alternate attitude control methods. The project has engaged in an intensive campaign to reduce hydrazine expenditures, which has resulted in a significant increase in the hydrazine expected to be available for Ceres. Based on this work, studies provide good confidence that the required activities at Ceres can be completed. This paper describes post-Vesta operations, including measures taken to conserve hydrazine as well as other preparations for Ceres.

• 出版日期2014-11