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Top Ten Discoveries of the Mars Rovers
eldavojohn writes "Space.com brings us the top ten discoveries of the Martian rovers that landed there in 2004. They were expected to last three months but, as Slashdot has covered time and time again, they have lasted over three years. From minor discoveries about the formation of Mars to images of atmospheric phenomena, to final and definitive proof of a Mars with water, these two robots have definitely reserved themselves a place in the history books. Pending a dust storm, they may not even be done with their mission yet."
10 - Opportunity provides tantalizing glimpse of Victoria crater.
9 - Evidence of volcanic origin for Gusev crater.
8 - First meteorite identified on another planet.
7 - Discover of sulfur suggests Mars stink.
6 - Helps scientists determine that Mars had three distinct geological eras.
5 - Martian dust devils captured on film.
4 - First shot of Earth from distant planet.
3 - Photographs Earth-like clouds on Mars.
2 - Helps scientists create first atmospheric temperature profile of Mars.
1 - First definitive evidence that water flowed on mars, including blueberries, hematite, and silica.
Ok, not to diminish the validity of the "Scotty method" of project estimating, but someone should probably once again join this discussion to clarify this point:
The mission plans called for a minimum of 90 days operations and a certain amount of driving (400 meters IIRC). This was not a prediction of the actual performance, but the criteria for mission success. Less than that would be considered only partially successful.
However, they did expect the rovers to last longer, based on the performance of Pathfinder and Sojourner, and therefore included an operations budget extension of 90 days in the budget. Not exactly a secret. By this time they figured it was about 50/50 whether dust accumulation would have robbed them of too much power or something would've broken, so the budget had an allowance for another extension of 180 days just in case.
At this point, they were pretty sure the rovers would be dead. NASA actually had to get special approval from congress to fund an additional one year of operations funding. Well guess what happened when that year was up. Yep.
So now they've gone 14 times the mission success criteria and 3-1/2 times NASA's best predictions. Opportunity has had a disabled heater on its infrared spectrometer for a while, Spirit has had a dead wheel motor for well over a year, and both of the rock abrasion tools are worn out from so much use, but they're still ticking. Of course, there is a real danger from the dust storm currently enveloping the planet, but I've got my fingers crossed.