What could have happened to the atmosphere and water on Mars?

[sandyRoe]

http://news.uk.msn.co...am-discovered-on-mars

[deggers316]

mars lost its atmosphere hence it liquid water evaporated but ice that was under the ground then could still be there

http://www.startrek.c...r_1245188351_33332070

[jake-the-peg]

Mars is smaller than Earth it's core was not able to keep going as long as our has

Once it was a volcanic planet - the largest known extinct volcano is there - but these days its core has cooled and the long term carbon cycle has stopped.

This meant that its temperature dropped and it froze

[wildwood]

If the planet is frozen, where do the little green men live?

[ll_billym]

Indoors.

[whiskeryron]

WR.

[douglas9401]

Hang on! If there's no water how do they make Smash? I'm beginning to doubt this wee green men story.

[jomifl]

The smash beings are silver/gey. You need to eat more smash to correct your colour vision.

[sandyRoe]

More carrots, surely?

[EDDIE51]

Mars is smaller than Earth and its gravity was is weak too permanently hold on to the atmosphere and water , it all floated off into space over a million years or so.