Venus Express Options

[tedstryk]

If all goes well, Venus Express will be a major topic for discussion in this forum a year from now. Does anyone know how good the surface coverage will be from VIRTIS and VMC? My understanding is that VIRTIS will obtain low resolution multispectral maps, and that VMC will, in addition to cloud monitoring, have one channel that can see the surface, but I don't know at what resolution or at what quality. It will be nice to have some non-radar images of Venus' surface besides the Venera snapshots and the shadowy images from Earth and Galileo's NIMS.

Ted

[RNeuhaus]

The spacecraft Technical details

Spacecraft facts
Spacecraft bus dimensions 1.5 x 1.8 x 1.4 m
Spacecraft mass 1270 kg (including 93 kg of payload and 570 kg fuel)
Thrust of main engine 400 N
Attitude thrusters Two sets of four, each delivering 10 Newtons each
Solar arrays Two triple-junction Ga As;
5.7 square metres; generating 800 Watts
near Earth and 1100 Watts at Venus
Power storage Three lithium-ion batteries
Antennas Two high-gain dishes, HGA1 = 1.3 m diameter,
HGA2 = 0.3 m in diameter, 2 low-gain antennas

Venus Express

The proportion of total weight versus fuel is 44.8% of weight is fuel comparing to the MRO (1,187 kg of fuel hydrazine of 2,180 kg = 54.4% to reduce 1.4 KM/sec during the orbit insertion.) I have not found how the Venus Express will insert into the Venus. At what speed and the what orbit will be traveling VE (Polar, some inclination Equatorial).

The panel solar is very small : 5.7 M^2 versus 10 M^2 of MRO. VE will have about 1,100 Watts and MRO around 1,000 Watts of power when these spacecraft are in their orbits. VE uses Lithium-ion batteries and MRO uses Nickel-hydrogen batteries. What is the difference?

Rodolfo

[um3k]

The panel solar is very small : 5.7 M^2 versus 10 M^2 of MRO. VE will have about 1,100 Watts and MRO around 1,000 Watts of power when these spacecraft are in their orbits. VE uses Lithium-ion batteries and MRO uses Nickel-hydrogen batteries. What is the difference?

Rodolfo

I'm no expert, but I would venture to guess that the cause is the spacecrafts' distances from the sun.

[Rakhir]

I'm no expert, but I would venture to guess that the cause is the spacecrafts' distances from the sun.

From the pdf of my previous post : "The sun is twice as strong at Venus as on Earth, so there is plentiful solar radiation to power the spacecraft. VE's solar arrays could therefore be made smaller (almost half the size) than those on Mars Express."