Credit: NASA/JPL/University of Arizona
Future human crews strolling around on Mars need to keep an eye on the Martian sky – for one they’ll have to be on the lookout for incoming objects.
NASA’s Mars Reconnaissance Orbiter (MRO) has spotted a cluster of impact craters that formed sometime between August 2005 and November 2010.
The new craters were first discovered in a MRO Context Camera (CTX) image.
According to Alfred McEwen, a leading planetary scientist at the University of Arizona in Tucson: “What’s unusual about this site is that it isn’t as dusty as most places where new impacts are discovered. Often the airblast disturbs the dust to create a dark spot much larger than the crater and its ejecta…so the new impacts are most easily discovered over dusty terrains.
McEwen is principal investigator of the High Resolution Imaging Science Experiment (HiRISE) for the MRO.
“The dark ejecta is obvious while the larger dark spot…is subtle, but detectable in the CTX image. There is a tight cluster of craters rather than a single crater because rocky bolides often break up in the Martian atmosphere,” McEwen noted on November 7, detailing the observation on MRO’s HiRISE website.
McEwen explains that the high-velocity collision of interplanetary objects — mostly asteroids, also comets — with the surface of Mars creates primary impact craters. The primary impacts may eject significant numbers of rocks at high velocity which fall back to make secondary craters.
By Leonard David