NASA To Try Powering Mars Rover "Spirit" Out of Sand Trap

coondoggie writes "NASA's long-running Mars rover Spirit is stuck in a sand trap — a situation the space agency would like to fix. Yesterday NASA said it will begin what it called the long process of extricating Spirit by sending commands that could free the rover. Spirit has been stuck in a place NASA calls 'Troy' since April 23, when the rover's wheels broke through a crust on the surface that was covering bright-toned, slippery sand underneath. After a few drive attempts to get Spirit out in the subsequent days, it began sinking deeper in the sand trap. Driving was suspended to allow time for tests and reviews of possible escape strategies, NASA stated."

Re:Just goes to show

[DNS-and-BIND]

They get stuck too. Difference is, they've got a buddy with his own 4-wheeler and tow chains. Maybe they need to send these things in pairs...

Re:NASA Quality & Space Commercialization

[jdigriz]

Guys, the 90-day planned lifespan of the rovers was pure politics. Congress wouldn't have gone for, "Yeah, we're gonna need funding for the next 5 years." if told so up-front. At the same time, it wouldn't have made sense to allocate that money from the beginning since there was a non-zero chance that the rovers might auger in, like the Mars Polar Lander did, and that none of that funding for surface ops would be needed after all. So they built the rovers, said "Well, if we get 90 days out of them, we can declare Mission Accomplished." and went with it. Since they were solar-powered there's no particular reason that they would last only that long. 90 days was a classic case of "underpromise and overdeliver." If there had been some sort of catastrophic design flaw and they failed after only 30 days they could have claimed to have succeeded with 1/3 of the mission objectives, etc.

Re:NASA Quality & Space Commercialization

[Anonymous Coward]

While that may be true, nonetheless 5 years of operation on Mars is damn impressive.
"Underpromise" or not, they certainly overdelivered

Re:NASA Quality & Space Commercialization

[AikonMGB]

The problem isn't politics, it's requirements. In order meet a requirement like mission length, you have to show that the system will be X% capable of operating for the desired life span (where X is defined by your customer). To show that a system is capable of surviving 90 days on Mars is likely multiple orders of magnitude cheaper than to show that a system is capable of surviving 5 years. Right off the bat, you would need

• increased solar panel area to deal with end-of-life conditions, both cell degradation and environmental effects;
• more, bigger batteries to ensure that they can maintain sufficient charge after 5 years;
• more expensive electronic components that can handle higher radiation doses, and more electronic redundancy to protect against single-event faults;
• redundancy of moving parts critical to the mission (e.g. wheel motors); and,
• as you mentioned, ground operations, both personnel, equipment, and antenna time.

This is just what I thought of in the 60 s it took me to write this post -- I'm sure there are many more factors anyone could dig up. The point is that aiming for 5 years, even with intent of only operating it for 90 days, would drive the cost up prohibitively.

Aikon-