WASHINGTON (Reuters) - It made a big splash when scientists announced in 2006 that images from a NASA spacecraft indicated water apparently had flowed on the surface of Mars in the past decade but new research casts doubt on that finding.

Link:  http://news.yahoo.com/s/nm/20080229/sc_nm/mars_water_dc

 I think that the truth about whether there is or has been surface water on Mars recently will not be known for years or decades. We still know so little about that planet.