Spiders on Mars

Mars has long fascinated the people of Earth, in the beginning owing to its reddish color in the night sky, and then, as we learned more about it, the possibility that it once held life and liquid water on its surface. Mars continues to hold the minds of many scientists mystified with its secrets, as new images are produced ever day from various missions to the Red Planet.

Mars also has a history of providing Earthlings with odd and interesting structures, one of the most infamous being the ‘face’ on Mars. Originally thought to be evidence of a sentient culture on Mars, it was later debunked by scientists proving it was the way the shadows crossed the structure that made it appear like a face. Recently, images from the Red Planet show very strange, spider-like etchings in the surface of the planet. Until a few days ago, the strange markings perplexed planetary scientists and defied explanation. However, thanks to new observations from the Mars Reconnaissance Orbiter, new light has been shed on the mysterious wiggles.

Because Mars experiences seasons, like the Earth, it goes through periodic warming and cooling of its ice caps. Much of the ice on the Martian surface is frozen carbon dioxide, which sometimes skips right past its liquid phase when it is heated. In the Martian spring, when the polar caps are facing the sun, light from the sun heats the caps. Because of the nature of the polar caps, the light passes through the top layers and penetrates to the darker Martian rocks under the ice. This causes the ice to heat from below, and instead of melting, the ice sublimes, or goes immediately into a gas.

When gas builds in a closed environment, it puts a great amount of pressure on the walls of that environment. In this case, the walls are the Martian surface. The gas causes too much strain it actually forces cracks in the terrain so that it can escape. Scientists think this is the method that causes the interesting spider-like structures that have been seen on Mars. After the springtime, when summer on Mars approaches, the sun causes the ice to completely evaporate, and leave behind the cracks and fissures it caused.

The theory surrounding the spiders on Mars is important to understanding more of Mars. If we can understand more about Mars, we can learn how better to support human life there in the near future. Studying the Martian surface may also give us clues as to how our own planet will look in the future, as we are slowly spiraling towards the same fate. (Slowly, very, very slowly)