28 February 2009
I’m falling behind on my blogging of the MOC “book”! We read a lot this week, so I will just stick to the highlights. In other words: mostly pictures, less text. This paper is really all about the pictures anyway! (if you’re just tuning in to the MOC series, check out posts 1,2,3 and 4)
The Martian poles are extremely fascinating but extremely bizarre places. The polar caps are made of water and CO2 ice, and as that ice freezes and thaws, it forms some strange landscapes.
The north and south polar caps are very different-looking, and there is no good explanation for why. This image shows layers from the south and north polar cap. The southern layers are very rough and rugged-looking, while the north polar layers are much smoother.
The layers in the north polar cap are amazingly coherent. They can be traced for hundreds of kilometers in some places:
Not all of the polar layers are perfectly flat, though. There are some examples of layers that have been deformed, or which intersect with each other, implying that they were subject to tectonics and erosion between periods of deposition.
The paper had a lot of observations, but not many conclusions about the Martian poles. The poles are still not well understood, though missions like Phoenix and MRO are helping to shed some light on the mysterious processes that shape the polar regions.