ESA Venus Express Status Report No. 81 – Swap to HGA2
14 Jun 2007 15:28
Report for Period 27 May to 2 June 2007
The swap from High Gain Antenna 1 to High Gain Antenna 2 took place during this reporting period, and proceeded according to plan. A single Cebreros pass was skipped to increase cooling of VIRTIS for operation. The use of “delayed TC files” as part of the quadrature operations has worked very well during this period, loading all the operations for an entire week in a single day (31 May).
The table below shows a chronology of the main activities in the reporting period:
| MET (Day) | Date | DOY | VPER# | Main Activity |
| 565 | 27/05/07 | 147 | 394 | Routine Mission Operations |
| 566 | 28/05/07 | 148 | 395 | Routine Mission Operations |
| 567 | 29/05/07 | 149 | 396 | Pass skipped for cooling |
| 568 | 30/05/07 | 150 | 397 | Routine Mission Operations. Upload of HGA swap products |
| 569 | 31/05/07 | 151 | 398 | Routine Mission Operations. |
| 570 | 01/06/07 | 152 | 399 | Routine Mission Operations. HGA swap performed at acquisition of signal |
| 571 | 02/06/07 | 153 | 400 | Routine Mission Operations |
At the end of the last Cebreros pass in the reporting period (DOY 153, 18:00z) Venus Express was orbiting Venus at 114 million km from the Earth. The one-way signal travel time was 380 seconds.
Payload Activities
ASPERA
The instrument was regularly operated as part of the routine plan.
Over the course of three days, from DOY 150 to 152, two ASPERA thermal telemetry parameters (Scanner and DPU) reported Out-of-Limit conditions at switch on. Due to safety concerns, the operation of the payload was temporarily disabled between DOY 152 and 154.
It is thought that recent extended Earth pointing periods in tilted attitude (immediately prior to the swap of the High Gian Antenna) have resulted in deeper than usual cooling of this unit. This results in temperatures lower than allowed at switch on, when ASPERA operations are started during Earth pointing phase. Otherwise the instrument is in good condition.
MAG
The instrument was regularly operated as part of the routine plan.
PFS
This instrument was OFF and was not operated.
SPICAV
The instrument was regularly operated as part of the routine plan.
VeRA
Occultation observations were performed over New Norcia on DOY 148, 150 and 152. Two RSI passes were supported from the Canberra 70-m DSN station on DOY 147 and 151.
VIRTIS
The instrument was regularly operated as part of the routine plan.
Future Milestones
Special operations are planned during the observations by NASA’s Messenger spacecraft on 5 and 6 June.
Quadrature phase operations will continue up to 16 June, DoY 167.
PFS test are being prepared to try to move the scanner during a wheel off-loading (WOL).
