November 1, 2012
ESA Images Show Evidence Of Mar’s Cold And Watery Past
Brett Smith for redOrbit.com - Your Universe Online
New images from the European Space Agency´s Mars Express orbiter show evidence of the Red Planet´s glacial past and ancient waterways.The images and computer-generated perspectives depicted on the ESA´s website are focused on Nereidum Montes , a mountainous range that stretches over 700 miles. The area is known for its many gullies that some believe were created or eroded by water flow.
According to ESA, the new images show “a portion of the region, displaying multiple fluvial, glacial and wind-driven features.”
They also portray, in great detail, drainage patterns that were formed when water flowed into the deeper recesses of Nereidum Montes. The scientists noted that drainage patterns seen in these images resemble those on Earth that occur after a heavy rainstorm or rapid ice and snow melt. This leads them to believe that these same events took place on the Martian surface.
In addition to the drainage patterns, several craters in the area show “concentric crater fill,” a uniquely Martian phenomenon distinguished by rings of surface fluctuations found within a filled crater. The different ratios between the diameter and depth of the filled craters indicate that ice or even ancient glaciers could be present and extend hundreds of feet beneath the surface debris, according to the scientists.
Another sign that surface water once existed on Mars was seen in a phenomenon called fluidized ejecta seen around some craters in the images. Fluidized ejecta is often marked by a small ridge that forms along the margin of material ejected around a meteorite impact site. Scientists believe that fluidized ejecta is caused by the meteorite striking a surface that contains water. The water may have been underground, and could have been frozen or liquid. The impact releases this water, along with surface material, causing the ejecta to flow across the surface of the planet like mud.
The images also show other features of the Martian surface in great detail, including large field of sand dunes that are located along the wind-sheltered sides of some geological formations.
The Mars Express was launched in June 2003 on a Soyuz-Fregat rocket and was named for its relatively rapid and streamlined development. The Mars Express is scheduled to perform its mission of studying the Red Planet until 2015. It also represents the ESA´s first visit to another planet in the Solar System.
The orbiter´s primary mission is to “answer fundamental questions about the geology, atmosphere, surface environment, history of water and potential for life on Mars,” according to a statement of the ESA´s official website.
Mars Express will also likely serve to lay the groundwork for any future robotic or human explorers to visit Earth´s neighbor, the ESA said.
The Mars Curiosity rover, NASA´s current high-profile visitor to Mars, recently began conducting a series of tests on the surface soil there. The rover is equipped with a scoop that can collect a sample of the surface and then send that sample to several different testing locations on the vehicle. Preliminary tests have shown that the Martian soil bears some resemblance to volcanic soil here on Earth.