Timeline of events during the Venus Orbit Insertion (VOI) manoeuvre, marking arrival of ESA’s Venus Express spacecraft at its destination on 11 April.
VOI is a series of telecommands, engine burns and manoeuvres designed to slow the spacecraft from a velocity of 29 000 kilometres per hour relative to Venus to an entry velocity some 15 percent slower, allowing it to be captured into orbit around the planet.
|
Time (CEST) |
Event |
|
09:17 |
VEX main engine burn starts Venus Express’s main engine is due to fire for approximately 51 minutes. |
|
09:45 |
Occultation starts (loss of S-band signal) An occultation occurs when Venus Express travels behind the planet so that the line of site to Earth is blocked; it will lose radio contact (S-band) for almost 10 minutes. During the journey to Venus, communication has been in X-band, via the high-gain antenna HGA2. During VOI, communications reverted to S-Band. |
|
09:55 |
Occultation ends Controllers will closely watch for reacquisition of radio contact once the occultation ends. |
|
10:07 |
VEX main engine burn ends |
|
10:10 |
Announcement by Flight Operations Director |
|
11.07 |
X-band transmitter on S-band provides omnidirectional coverage for both up and downlink over small distances, while X-band provides a high-rate data downlink and a telecommand uplink while in Venus orbit. |
|
11:12 |
Telemetry received |
|
11:30-12:15 |
Press Conference |
All times above are ‘Earth Received’ time – i.e. after the actual events
have taken place at the spacecraft. During orbit insertion, the
spacecraft will be 125 000 000 kilometres from Earth and the round-trip
signal time will be 13 minutes and 32 seconds.
