The Planetary Society’s Report has reminded me that there’s more going on than politics – there’s the greater Universe. I’ll be scattering some cool pictures from 2016 about, just to keep up my feeling of awe. First up is from NASA/JPL/University of Arizona and the MRO HiRISE project, looking at the Martian south polar region:
Source: NASA/JPL/University of Arizona
The white portions of this observation are part of that residual [South Polar] ice cap, and the sunlight is coming from roughly the bottom of this non-map projected image. It is made of solid, frozen carbon dioxide and is very bright relative to the background. This is despite the background terrain having a very high water-ice content, which is darkened by very fine rocky particles, or dust.
Very interesting and picturesque in this scene are the different scales of polygons present in each terrain. The relatively medium-toned lines in the dark terrain divide it into polygons that are up to approximately 10 to 15 meters (30 to 45 feet) wide. Typically, temperature changes of the ground over the seasons cause it to expand and contract, forming cracks and troughs between sections of ground that may partially fill with frost, forming the polygonal pattern viewed from above.
The polygons in the bright carbon dioxide terrain are different. First, they are much larger, up to 20 to 40 meters (60 to125 feet) wide.
Very unexpected.
