Mars' Seasonal Cap of Carbon Dioxide (CO2) Ice erodes a lot of South Polar Terrains as it Sublimates (meaning that it goes directly from Ice to Gas) at every Spring. In this South Polar Region where the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's - Mars Reconnaissance Orbiter took this image, we can see several Troughs (---> Steep-walled Channels) that form a Starburst Pattern (such as a drawing resembling to an exploding Star). In other areas these Radial Troughs have been refered to as "Spiders", simply because of their shape. In this Region, instead, the pattern looks more Dendritic (meaning a multi-branching tree-like form) since Channels branch out numerous times as they get further from the center of the Surface Feature. The Troughs are believed to be formed by some Natural Gas (Methane maybe) flowing beneath the Seasonal Ice until it reaches some cracks (openings) from which it escapes, carrying along Dust and small rocks (pebbles), both picked during its (likely) very fast flowing in the Sub-Surface. The Dust and the Pebbles carried by the Gas, after the Outburst (---> Outgassing), fall back on to the frozen Surface in Fan-shaped Deposits. Just out of curiosity, it is important to remember that this specific kind of Surface Feature was, for a long time - and, in a way, still is, following and according to the absurde speculations of a few "pseudo-Researchers" -, thought to be the evidence of some form of Martian Vegetation (Martian Trees, to be precise). It is absolutely obvious that this claim (which, in our opinion - as IPF -, totally lacked of an even minimal substance), must be considered just as one of the many "Martian Legends", created for the only purpose of making some easy money by selling fairy-tales and pure nonsense to an (unfortunately) very large population of certainly enthusiastic, but also totally untrained (and therefore unfamiliar with this specific, and really difficult, Matter), Space and UFO Fans.
This image, covering an area of about 1 Km (approx. 0,6 miles) across, is just a portion of the HiRISE observation catalogued as ESP_011842_0980, and taken on February 4th, 2009.

 

Mars Local Time: 16:56 (Middle Afternoon)
Coord. (centered): 81,8° South Lat. and 76,1° East Long.
Spacecraft altitude: 248,3 Km (such as about 155,2 miles)
Original image scale range: 49,7 cm/pixel (with 2 x 2 binning) so objects ~ 1 mt and 49 cm across are resolved
Map projected scale: 50 cm/pixel
Map projection: POLAR STEREOGRAPHIC
Emission Angle: 4,9°
Phase Angle: 82,2°
Solar Incidence Angle: 78° (meaning that the Sun was about 12° above the Local Horizon at the time that the picture was taken)
Solar Longitude: 203,6° (Northern Fall)
Credits: NASA/JPL/University of Arizona