Mars Orbiter Finds Buried Dry Ice Lake

RedEaredSlider writes "NASA's Mars Reconnaissance Orbiter has found a giant buried deposit of dry ice, which could be evidence that Mars once had a thicker atmosphere and was able to have more water on its surface. The orbiter's ground-penetrating radar found the dry ice, which is frozen carbon dioxide, near the planet's south pole. The scientists think that when Mars' axial tilt increases, the carbon dioxide turns into a gas, thickening the atmosphere. The result would be more intense dust storms, but also a wider range of areas where liquid water could exist."

Comments

Regarding the atmosphere..

[Anonymous Coward]

Mars isn't protected by a strong magnetic field like Earth is.. meaning the atmosphere is frequently subjected to solar winds and radiation.. meaning any thickening of the atmosphere is not likely to remain constant for any meaningful time period.

Re:Regarding the atmosphere..

[jd]

In the early days, the Martian core would not yet have solidified. Thus, the magnetic field would have been substantially stronger. The fact that it's still semi-liquid today (as evidenced by the fact that there's any magnetic field now at all) is the remarkable part of the story. 3-4 billion years ago, the Martian magnetic field would likely have been far more intense than Earth's is today. Hell, Earth's magnetic field a paltry 220 million years ago was 33% stronger than present by some estimates, and Earth's core is heated by thermonuclear activity. The Martian core likely isn't to any meaningful degree.

Back when briney oceans formed the Martian surface (we already know that part), Mars would have been a bad place for floppy disks.

Re:Terraforming 101

[alostpacket]

Wouldn't the problem be that the solar wind would just blow away the atmosphere? From what I understand Mars has a very weak and unstable magnetic field (unlike the Earth). http://science.nasa.gov/science-news/science-at-nasa/2001/ast31jan_1/

Re:It'd be more interesting if ...

[LWATCDR]

Umm... Gold is cheap compared to interplanetary travel. Heck even if you found a mountain of diamonds the size of basketballs it still wouldn't be worth it. I think gold would have to hit something like $100,000 and ounce to make hauling it from the moon practical. And rare earths? Just not that rare and no most currencies are not backed by gold reserves.