[Rockhounds] Glaciers found on Mars

[Kreigh Tomaszewski]

The more we learn about Mars, it seems, the icier the Red Planet 
appears to be. The recently departed Phoenix lander dug up water ice 
and even spotted falling snow from its position in the northern polar 
plains. And now data from the Mars Reconnaissance Orbiter point to vast 
glaciers buried beneath thin layers of crustal debris, much closer to 
the equator.

  The findings, published today in Science, come from the spacecraft's 
shallow radar, or SHARAD, which is able to penetrate the surface and 
examine what lies beneath. In this case, SHARAD indicated that two 
long-visible mid-latitude features, one of which is roughly three times 
the size of Los Angeles, are almost completely composed of water ice. 
(The suspect glaciers are covered by debris that obscures them but also 
insulates the ice from sublimating into water vapor, much as street 
grit forms an opaque, protective blanket over roadside snowbanks.)

http://www.sciam.com/article.cfm?id=red-planet-alert-massive