No. 146 - Outcome of Atmospheric Drag Experiment
The table below shows a chronology of the main activities in the reporting period:
| MET (Day) | Date | DOY | Main Activity |
| 1020 | 24/08/08 | 237 | Routine Operations |
| 1021 | 25/08/08 | 238 | Routine Operations |
| 1022 | 26/08/08 | 239 | Routine Operations |
| 1023 | 27/08/08 | 240 |
Routine Operations |
| 1024 | 28/08/08 | 241 | Routine Operations |
| 1025 | 29/08/08 | 242 |
Routine Operations |
| 1026 | 30/08/08 | 243 | Routine Operations. Telemetry bit rate updated to 91 kbps before acquisition of signal at ground station |
At the end of the last Cebreros pass in the reporting period (DOY 243) Venus Express was orbiting Venus at 230.9 million km from the Earth. The one-way signal travel time was 769 seconds.
Atmospheric Drag Experiment
This reporting period marked the end of the atmospheric drag experiment (ADE) measurement passes associated with the pericentre altitude lowering campaign. The flight dynamics team has evaluated the drag effect on the spacecraft's apocentre altitude. Their assessment on 25 August 2008 concludes:
The pericentre altitude has now been close to 185 km for nearly 3 weeks. Small levels of atmospheric drag were estimated from the spacecraft tracking data gathered during the first two weeks. These drag levels were enough to reduce the apocentre altitude by a little under 10 metres at each pericentre passage. During the last week it appears that the reduction was slightly more than 10 metres at each pericentre passage - but still a very low level of atmospheric drag.
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 observations were made during the reporting period.
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
- High gain antenna (HGA1) S-band carrier power test is planned for 15 December 2008
- Next quadrature phase will start on 19 December 2008
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Legal disclaimer
This report is based on the ESOC mission operations report, MOR #146. Please see the copyright section of the legal disclaimer (bottom of this page) for terms of use.