[X] My Assistant

[Guest_Zvezdichko_*]

Well, that's a tough question. What will happen, for example if Mars Phoenix fails to touch down successfully? Maybe I look a bit pessimistic, but I like to think in perspective. I think that:

1.If MSL managers give up the skycrane and decide to use Phoenix-like pinpoint landing system, it will effectively move the launch date from 2009 to 2011. Since there's no NASA orbiter planned for launch in 2009, maybe we won't have a new spacecraft then.

2. It will end the scout program or... the next scout mission will be a simple orbiter.

3. There will be several small landers in future, using the good old airbag bouncing method.

[dvandorn]

Actually, using airbags is good for any experiments where hydrazine and other rocket exhaust end-products would contaminate the ground and make it more difficult to find what you're looking for in the soils around the lander. As it is, Phoenix data will have to be adjusted somewhat to filter out the observed effects of rocket exhaust on the soils that will be studied.

The odd part of this equation is that you want soils undisturbed by rocket exhaust for your heavier landers, while you're not nearly as concerned about the issue if you're just deploying things like seismometers and weather stations. So, in that regard, rocket landers are more appropriate for netlander-style small stations, while airbags are more suited to larger payloads. Unfortunately, the physics and engineering of the landing systems are exactly the reverse, with airbags more suited to small landers and rocket-assisted landings more suited for large, complex landers.

I think the solution is basically to make large landers which would benefit from undisturbed soils at least somewhat mobile. The problem there is that you spend an awful lot of your mass budget making your probe mobile, which means you have less mass than you'd like for experiments.

-the other Doug