Second man to step out on the moon, "Buzz" Aldrin, claims that there is a "Monument" or "Monolith" (aka shades of the movie "2001 A Space Odyssey"), in a recent photograph release by NASA. One of the reasons Buzz Aldrin is now saying we need to skip the moon and go straight for Mars now.
Check out the article on the British newspaper/website The Sun for more details. There was a special picture taken by the super high resolution camera on the Mars Reconnaissance Orbiter and a closeup image of the reportedly five meter tall object on the surface of Mars is convincing.
NASA wanted to downplay the report. It is a boulder that has weather and craked in such a way as to appear as the 2001 monolith is basically their take on it.
Ref. article from The Sun by Vince Soodin, Aug. 5, 2009. (http://www.thesun.co.uk/sol/homepage/news/2572537/Mars-monument-proof-of-life.html)