Is it raining on Mars?

Could there be clouds on Mars? The Mars Express satellite has detected that there is plenty more water vapor in the Martian atmosphere than previously expected. We have no evidence that there has been rain fall on Mars, so how did it get there?  What will happen to this vapor over time and will it all be lost to space?  Also, the new ALMA telescope, a very powerful millimeter/submillimeter-wavelength telescope trained to measure tiny wave lengths, is located in Chile where the atmosphere is very high and dry. So, what are we using the ALMA telescope for? Far out in space, in galaxies, there are molecular clouds that are incredibly dense, inside are leftovers of stars that have exploded. The millimeter telescope allows us to see through that cloud and observe the process that leads to making stars. And don’t miss what’s in the night sky this week. All this and more on this week’s Sky Talk.[audio: st20111010.mp3]