Meteorites on Mars ☆ ♂ ☆ ───────────────── by Robert Cattrysse. The rovers Spirit, Opportunity, and Curiosity have roamed around the landscape of the red planet Mars for some good distances. Opportunity and Curiosity continue to do so today. Besides studying soil, different types of rocks, and rock layers, they occasionally come across interesting extraterrestrial rocks. That is, they come across rocks that are not from Mars. They are meteorites that have fallen from space through the Martian atmosphere perhaps recently or in the distant past. These meteorites may become buried in or covered by Martian soil. However, ones on the surface may also have the soil blown off by Martian dust devils or wind, just like the rovers themselves have the dust and soil cleaned off themselves once in a while. Suddenly, and unexpectedly, a rover may come across and discover one of those meteorites. Here is an exciting opportunity for the instruments on the Mars Science Laboratory, the Curiosity rover, to examine a different part of our solar system in its discovery of a rather large meteorite with a smaller one lying beside it. This first meteorite discovered by Curiosity is about 2 metres across or from left to right in this photo. Scientists have named it Lebanon with the smaller meteorite in the foreground given the name Lebanon B. The iron meteorites are photographed here on May 25, 2014 during the 640th Martian day since Curiosity landed in Gale Crater located on the plain called Aeolis Palus. The circular images are high resolution photos taken by the Remote Micro-Imager (RMI) of Curiositys Chemistry and Camera (ChemCam). They are combined here with an image from the Mast Camera (Mastcam). The high resolution images clearly show the angular shaped cavities on the surface of the meteorite. NASA says one possible explanation for the features is that they resulted from preferential erosion along crystalline boundaries within the metal of the rock. They also state another possibility could be that these cavities once contained crystals of the mineral olivine. These can be found in a rare type of stony-iron meteorites called pallasites and are thought to have been formed near the core and mantle boundary within an asteroid of which this particular meteorite may have originated from. Most of the small number of meteorites located on Mars by robotic explorers are iron meteorites. One reason could be is that iron meteorites require much more time to erode from the Martian weather processes. On Earth stony meteorites are more common than iron meteorites. This photo was released on Tuesday, July 15, 2014 by the National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL) of the California Institute of Technology (Caltech). Photo courtesy of NASA/JPL-Caltech/LANL/CNES/IRAP/LPGNantes/CNRS/IAS/MSSS.
Posted on: Sat, 19 Jul 2014 08:42:20 +0000
Trending Topics
Recently Viewed Topics
© 2015