No. 106 - Gravitational Microlensing Observations Completed
10 October 2008 12:11
Report for Period 20 September 2008 to 5 October 2008
The reporting period covers two weeks of activities mainly dedicated to the OSIRIS gravitational microlensing event observations.
The spacecraft and ground segment performance during the reporting period have been nominal. Mission operations were conducted with the support of the ESA New Norcia (NNO) ground station.
At the end of the reporting period (DoY 279) Rosetta was at 414.2 million km from Earth (2.76 AU) and the one-way signal travel time was 1382 seconds. The distance to the Sun was 329 million km (2.19 AU).
The spacecraft will be configured to low activity cruise and the attitude and orbit control system (AOCS) will be switched to attitude control on 3 wheels. The spacecraft will then continue its fourth orbit around the Sun reaching aphelion on 17 December 2008 at a distance of 2.26 AU. It then heads back to Earth for the mission's last gravity assist and third Earth swing-by on 13 November 2009.
The angular separation between the spacecraft and the Sun will stay below 3° (conjunction) between 17 December 2008 and 6 January 2009 with the minimum angular separation (1.6°) occurring on 28 December. No special activities are planned for this conjunction phase during which short weekly passes will be taken.