ESA Venus Express Status Report No. 106 – End of Quadrature Operations
12 Dec 2007 08:49 Report for Period 18 November to 24 November 2007 The activities during this week cover routine operations, skipping passes for cooling purposes and the end of the Quadrature Phase on 23 November. VIRTIS operations have continued during the period.
The table below shows a chronology of the main activities in the reporting period:
| MET (Day) | Date | DOY | Main Activity |
| 740 | 18/11/07 | 322 | Pass skipped for cooldown before science operations |
| 741 | 19/11/07 | 323 | Routine Operations |
| 742 | 20/11/07 | 324 | Pass skipped for cooldown before science operations |
| 743 | 21/11/07 | 325 | Routine Operations |
| 744 | 22/11/07 | 326 | Pass skipped for cooldown before science operations. OCM 12:55-15:55 UT, Δv=8.5 ms-1, executed at apocentre |
| 745 | 23/11/07 | 327 | Routine Operations. End of Quadrature |
| 746 | 24/11/07 | 328 | Routine operations |
At the end of the last Cebreros pass in the reporting period (DOY 328, 18:00z) Venus Express was orbiting Venus at 133.3 million km from the Earth. The one-way signal travel time was 444 seconds.
Orbit Control Manoeuvre
The purpose of the OCM, executed at apocentre on 22 November, was to lower the pericentre altitude by 138 km which would decrease the orbital period by 227 seconds. The manoeuvre had a nominal magnitude of 8.493 ms-1.
The calibration within the orbit determination showed a slight over-performance of 2.18% (+185.1 mms-1). The 1-sigma uncertainty on this result is 0.03% (2.6 mms-1). The decrease in pericentre was 3.0 km more than planned and the decrease in orbital period was 5.0 seconds more than planned. This will be compensated for with the reaction wheel off-loading during the next few weeks.
Payload Activities
ASPERA
The instrument was regularly operated as part of the routine plan.
MAG
The instrument was regularly operated as part of the routine plan.
PFS
The instrument was not operated during the reporting period.
SPICAV
The instrument was regularly operated as part of the routine plan.
VeRA
No RSI activities took place this week.
VIRTIS
The instrument was regularly operated as part of the routine plan.
VMC
The instrument was regularly operated as part of the routine plan.
Future Milestones
- Christmas period planning
- New Norcia and Cebreros scheduling for 2008
