Mars atmosphere grabs our spacecraft
Got an update on TGO aerobraking progress at mid-day today from Silvia Sangiorgi, our deputy spacecraft operations manager here at ESOC. She wrote:
PLM 1 [on 15 March] was nominal. [Since then] we have already had two percienter (= periapsis – point of closest approach above Mars) passes at 150 km height; they gave us, respectively, 11 and 10 mm/sec of delta V. All is nominal and working fine for the moment PLM 2 will be tomorrow at 11:45 UTC (12:45 CET); it will bring us a further 10 km down. Flight dynamics are producing the commands now – these will be uplinked tonight. Ciao, Silvia
Tomorrow's burn is planned to provide a delta-v (change in velocity) of 58 cm/sec and targets a pericenter hight of 140 km.
If the team are already seeing 'changes in velocity' due to the atmosphere on the order of 10 to 11 mm/second, then TGO is already 'feeling the burn'.
PLM refers to 'pericentre lowering manoeuvre' – how the engineers on the TGO team refer to the seven (planned) thruster burns that are slowing TGO, allowing it to sink, step-wise, lower in its orbit until atmospheric drag reaches a certain load. Then we'll be in aerobraking proper!
The seven manoeuvres are planned for:
- March: 15, 18, 21, 24 and 27
- April: 1 and 6
Read yesterday's blog post Hang 10 over Mars for full background.
Note that pericentre and periapsis, and apocentre and apoapsis are, when referring to Mars, often used interchangeably.
from Rocket Science http://ift.tt/2ma9r3I
v
Mars atmosphere grabs our spacecraft
Got an update on TGO aerobraking progress at mid-day today from Silvia Sangiorgi, our deputy spacecraft operations manager here at ESOC. She wrote:
PLM 1 [on 15 March] was nominal. [Since then] we have already had two percienter (= periapsis – point of closest approach above Mars) passes at 150 km height; they gave us, respectively, 11 and 10 mm/sec of delta V. All is nominal and working fine for the moment PLM 2 will be tomorrow at 11:45 UTC (12:45 CET); it will bring us a further 10 km down. Flight dynamics are producing the commands now – these will be uplinked tonight. Ciao, Silvia
Tomorrow's burn is planned to provide a delta-v (change in velocity) of 58 cm/sec and targets a pericenter hight of 140 km.
If the team are already seeing 'changes in velocity' due to the atmosphere on the order of 10 to 11 mm/second, then TGO is already 'feeling the burn'.
PLM refers to 'pericentre lowering manoeuvre' – how the engineers on the TGO team refer to the seven (planned) thruster burns that are slowing TGO, allowing it to sink, step-wise, lower in its orbit until atmospheric drag reaches a certain load. Then we'll be in aerobraking proper!
The seven manoeuvres are planned for:
- March: 15, 18, 21, 24 and 27
- April: 1 and 6
Read yesterday's blog post Hang 10 over Mars for full background.
Note that pericentre and periapsis, and apocentre and apoapsis are, when referring to Mars, often used interchangeably.
from Rocket Science http://ift.tt/2ma9r3I
v
Aucun commentaire:
Enregistrer un commentaire