NASA's Mars Reconnaissance Orbiter Detects Recently Formed Crater on Mars
NASA has released images from Mars that show a fresh impact crater on the planet's surface. Described as the "largest fresh impact crater ever clearly confirmed from before-and-after images" the research shows an 8 kilometer-wide darkened area on the surface of Mars that scientist Bruce Cantor noticed by chance after looking over images from the Mars Reconnaissance Orbiter. By skipping back through the archives of images snapped by the Orbiter's Mars Color Imager (MARCI), Cantor was able to identify the approximate date that the crater was created. The dark spot was showing up in MARCI images from 2013, but in images taken of the same area in 2010, there were no dark spots to be seen.
"It wasn't what I was looking for," said Cantor. "I was doing my usual weather monitoring and something caught my eye. It looked usual, with rays emanating from a central spot."
Upon closer investigation of the images, Cantor was able to locate the area in question from before the impact, and thereby pinpoint the exact date of the impact (March 27th-28th, 2012) using before-and-after imagery.
Between the HiRISE and CTX images, NASA was able to identify two larger craters, the bigger one spanning 48.5 by 43.5 meters, and "more than a dozen smaller craters near [them...], possibly created by chunks of exploding asteroid or secondary impacts of material ejected from the main craters during the impact."
Alfred McEwen, Principal Investigator of HiRISE, estimates the impact object that created the craters to measure just "3 to 5 meters long", but thanks to the Red Planet's weaker atmosphere combined with a strong explosion, the crater is far more significant than one might expect from an object of that size.