Mars Makes an Impact: Scientists Discover Hundreds of Craters on Red Planet

Mars is making less of an impact--at least as far as its craters are concerned. Scientists have identified almost 250 fresh impact craters on the Red Planet, which means that it's getting pummeled by space rocks far less frequently than previously thought.

In order to examine and record these craters, scientists used images from NASA's Mars Reconnaissance Orbiter (MRO). After studying the images, they found that the planet was, on average, bombarded by more than 200 small asteroids or bits of comets each year. These space rocks generally formed craters that were at least 12.8 feet across. Earlier findings actually pegged the cratering rate at three to 10 times more craters per year.

On Earth, most space rocks don't even make it to the ground. Our planet has a thick atmosphere, and asteroid or comet fragments typically burn up before they reach the surface. Mars, though, has a much thinner atmosphere. This means that the fragments, which are typically no more than three to six feet across, can slam into the Red Planet.

"It's exciting to find these new craters right after they form," said Ingrid Daubar of the UA, lead author of the paper, in a news release. "It reminds you Mars is an active planet, and we can study processes that are happening today."

The recent findings actually tell scientists quite a bit about Mars. Estimates of the rate at which new craters appear serve as scientists' best yardstick for estimating the ages of exposed landscape surfaces on Mars and other worlds. The study of these craters could also allow scientists to better understand what type of environmental factors may have shaped the surface of the Red Planet over time.

"Mars now has the best-known current rate of cratering in the solar system," said Alfred McEwen, co-author of the paper, in a news release.

The researchers plan to continue examining Mars. They hope that their study could lead to further scientific insight into some of the natural features on the Red Planet.

The findings are published in the journal Icarus.