Dubbed by the Mars HiRISE team as "Happy Face". Credit: HiRISE.

Dubbed by the Mars HiRISE team as "Happy Face". Credit: HiRISE.

Good morning, Earth people!

This week is a feature on the Swiss Cheese terrain on Mars! This terrain does not officially have the name "Swiss Cheese", but it is rather the end-product of a seasonal process on Mars. Yes, Mars does go through seasons, just not as visually stunning like we have here on Earth. To planetary scientists' surprise, Mars goes through seasonal changes on the surface, and the Swiss cheese terrain is one of them. This terrain consists of semi-circular or noodle-like pits across the surface.

Mars has polar caps, each with some ratio of frozen water and carbon dioxide. However, during the northern summer, the carbon dioxide will completely evaporate. So during the same time as a southern winter, the South pole gets colder with carbon dioxide, giving a bigger abundance of this ice. As this ice sublimates, or rather directly goes from solid to gas. This is a slow process and is found to sublimate at different rates. This makes for different Swiss cheese patterns! 

Circular and noodle pitting patterns of the Swiss cheese terrain. Credit: HiRISE.

Circular and noodle pitting patterns of the Swiss cheese terrain. Credit: HiRISE.

Here are some more facts about this weird terrain:

1.) It is ONLY found in the South pole region of Mars. Planetary scientists on Earth can not replicate it or find it anywhere on Earth as comparison.

2.) It is believed that the flat floors of the pits are the water ice and the rims and walls are dry ice and carbon dioxide. 

3.) Some have been observed to grow larger in time: about 1 to 3 meters per year! This gives us a chance to look into climate changes on Mars.

Beautiful water ice cracked floors of the pits and some double-ring features near the top-center of this image. Credit: HiRISE.

Beautiful water ice cracked floors of the pits and some double-ring features near the top-center of this image. Credit: HiRISE.

Thank you all for visiting and come back next week for a chat about Charon!