When Something Big Slammed into the Moon: Big Pic
NASA/GSFC/Arizona State University
July 6, 2012 — While in its new higher elliptical orbit, NASA's Lunar Reconnaissance Orbiter may be trying to conserve fuel but it's certainly not holding back on the amazing images!
The shot above — actually a mosaic of 8 separate images taken during 4 consecutive orbits — shows Giordano Bruno, a 21-km (13-mile) wide crater that may be the result of a comet or asteroid impact 10 million years ago. To us, that's a long time — longer than humans have walked on Earth. But to a 4.5 billion-year-old Moon, that's just yesterday!
Named for a 16th-century Italian Dominican friar who proposed that the sun is a star and the Universe contains other worlds with intelligent life on them (and was subsequently executed for doing so) Giordano Bruno crater is 8,200 feet (2,500 meters) deep — over 2,000 feet (600 meters) deeper than the Grand Canyon (if not quite as wide). The crater floor contains many interesting features from its formation, like impact melt flows and curious dark splotches of material… as well as plenty of boulder tracks from lunar rocks loosened over the millennia.