The Most Impressive Surface Features Of Mars
Alan McStravick for redOrbit.com – Your Universe Online
Scientists will never know who first looked to the heavens and noticed the pale pink, barely visible orb that graces our early morning skies. We do know the Greeks named the red planet Ares in honor of their god of war. It wasn´t until the Romans came on the scene and renamed this celestial sphere for their own god of war, however, that we came to know our heavenly neighbor as Mars.
Over the years, Mars has received a lot of human attention from both astronomers and laymen alike. In particular, humans have long been fascinated by the surface features of this distant planetary cousin to Earth. And why shouldn´t we be interested? It has many interesting geological formation. A few of the main surface features of Mars include mega volcanoes, enormous valleys and frozen polar caps.
As one takes a closer look at the surface of the red planet, enormous shield volcanoes become visible — so named because their appearance resembles that of a shield. While these volcanoes are extinct, they are indicative of a period of intense volcanism, the regular eruption of molten rock from deep within the planet. Most Martian volcanoes are much larger than volcanoes found on Earth. Experts theorize that this is due to the fact that Mars does not have a plate tectonic system like Earth does.
Another important feature of Mars´ surface is its vast network networks of large canyons. The largest, called Valles Marineris, extends approximately 3,100 miles and spans more than 300 miles across at its widest point. At its deepest point, Valles Marineris descends almost 4 miles into the Martian interior. Unlike Earth´s canyons, scientists long believed that erosion played little or no part in the formation of these large canyon systems. That said, evidence has recently come to light supporting the hypothesis that fluid erosion may have played at least some role in the formation of Mars´ canyons as well.
Current Martian atmospheric conditions preclude the existence of water as a free liquid. However, evidence of running water erosion, based on these channels´ similar appearance to our own terrestrial channels, suggests the atmosphere was significantly denser and more Earth-like at some point in the past.
Despite the thin nature of Mars´ atmosphere, high-velocity seasonal winds are still a possibility. They are generally stirred up by the solar heating of the Martian surface and are capable of producing dust storms. The dust storms, in turn, have been shown to be very effective at creating surface erosion.
Mars also has polar caps at both poles which increase and decrease in size in accordance with the Martian seasons. The polar caps appear to be made of frozen carbon dioxide, also known as dry ice, and frozen water. The north cap is covered by a relatively thin, one-meter layer layer of carbon dioxide during Mars´ winter months, while the south cap has a permanent layer of dry ice cover that is approximately eight meters thick. During the Mars summer time, the north polar cap has a diameter of about 625 miles while the southern polar cap is only about 220 miles across.
With orbital observatories like the International Space Station (ISS) and the Hubble Space Telescope, partnered with NASAs Mars probe and rover missions, researchers continue to uncover the secrets of Mars´ surface features.