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On a positive note, the dead wheel dug up Martian soil which enabled Spirit's most impressive discovery - a patch of nearly pure silica. This was most likely caused by hot springs or steam vents.
Spirit contained a rock abrasion tool and was able to drill into 15 different rock samples and analyze them.
Five years after this image was taken by Spirit in 2005, NASA scientists concluded that this area showed a past that was wet and non-acidic and could potentially sustain life as we know it. The rocks were identified as magnesium iron carbonate with a 10x higher concentration of carbonate that ever seen on Mars. NASA say "Carbonates originate in wet, near-neutral conditions, but dissolve in acid."