Habitable Mars

http://www.sciencedaily.com/releases/2013/05/130530150547.htm

May 30, 2013 — Detailed analysis and review have borne out researchers' initial interpretation of pebble-containing slabs that NASA's Mars rover Curiosity investigated last year: They are part of an ancient streambed.

The rocks are the first ever found on Mars that contain streambed gravels. The sizes and shapes of the gravels embedded in these conglomerate rocks -- from the size of sand particles to the size of golf balls -- enabled researchers to calculate the depth and speed of the water that once flowed at this location.

 

Water on Mars? For those of you who don't know, Mars does have an atmosphere. It is 95% Carbon Dioxide, with other various gases thrown into the mix. The idea of Mars having water goes far beyond just the idea of giving it streams and foliage. The idea that Water could have flowed on Mars means that, at some point in it's life, Mars may have housed more than just streams of water.

Understanding exactly what happened to Mars is pivotal to use understanding why our planet is still here to tell the tale. By all accounts, our planet is a statistical anomaly in the universe(less than one chance in 10 to the 139th power (ten thousand trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion). What we do know so far is that we are in the Habitable Zone, or the small zone where we're close enough to the sun to not freeze, but far enough away to not burn.

Mars is currently not inside of the Habitable Zone. A lot of questions are raised by this, however one question that piques my interest is: Was Mars ever IN the Habitable Zone to begin with? This of course begs other questions. If it was not, how could it have formed an atmosphere like it has? If it was, what moved it out of that orbit? 

Perhaps our understanding of Mars' fate will help us better understand our own planet Earth's.