- This set of images from cameras on NASA’s Mars Reconnaissance Orbiter documents the appearance of a new cluster of impact craters on Mars. The orbiter has imaged at least 248 fresh craters, or crater clusters, on Mars.Image credit: NASA/JPL-Caltech/MSSS/Univ. of Arizona The two upper images are from the orbiter’s Context Camera (CTX). Researchers investigated the new dark spot with the orbiter’s High Resolution Imaging Science Experiment (HiRISE) camera, obtaining the lower image showing a cluster of small, fresh craters. Image credit: NASA/JPL-Caltech/MSSS/Univ. of Arizona.
If you’re headed for a lengthy stay on Mars – head’s up!
Scientists sifting over images taken by NASA’s Mars Reconnaissance Orbiter (MRO) have estimated that the Red Planet is on the receiving end of more than 200 small asteroids or bits of comets each year.
Those impacts form craters at least 12.8 feet (3.9 meters) across.
The new research work is detailed by Ingrid Daubar of the University of Arizona, Tucson, lead author of a paper published online this month by the journal Icarus.
Researchers have identified 248 new impact sites on parts of the Martian surface in the past decade, using images from the spacecraft to determine when the craters appeared.
Planetwide estimate
The 200-per-year planetwide estimate is a calculation based on the number found in a systematic survey of a portion of the planet.
Hard at work is MRO’s High Resolution Imaging Science Experiment (HiRISE) camera taking pictures of the fresh craters at sites where before-and-after images by other cameras bracketed when the impacts occurred.
This combination provided a new way to make direct measurements of the impact rate on Mars. This will lead to better age estimates of recent features on Mars, some of which may have been the result of climate change.
“It’s exciting to find these new craters right after they form,” Daubar said in a university press statement. “It reminds you Mars is an active planet, and we can study processes that are happening today.”
“Mars now has the best-known current rate of cratering in the solar system,” said Alfred McEwen of the University of Arizona, a co-author on the paper. He is the HiRISE Principal Investigator.
The paper is published online this month by the journal Icarus at:
http://dx.doi.org/10.1016/j.icarus.2013.04.009
By Leonard David