Somebody looking at the pictures send from the rover noticed this detail if u look closely on the picture u will notice 194 written on the stone!...
There theories ranging from the was previous life on mars to nasa faked mars landing like they did the moon landing u decide for ur self!
2nd big stone from the top right corner
http://marsrovers.nasa.gov/gallery/a...9P2511R2M1.JPG
2nd big stone in the middle from the top aboe the cylender shaped object
http://marsrovers.nasa.gov/gallery/a...9P2512L2M1.JPG
http://marsrovers.nasa.gov/gallery/a...9P2511L2M1.JPG
if u don't belive me go to the nasa website urself
http://marsrovers.nasa.gov/gallery/all/spirit_p013.html