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> Mercury by Messenger- Jan 14 2008

Mercury by Messenger- Jan 14 2008

author: Nasa/JHUAPL/ Carnegie Institution of Washington/Novapix

reference: a-mer04-00007

Image Size 300 DPI: 15 * 8 cm

On January 14, 2008, the MESSENGER spacecraft observed about half of the hemisphere not seen by Mariner 10. These images, mosaicked together by the MESSENGER team, were taken by the Narrow Angle Camera, part of the Mercury Dual Imaging System (MDIS) instrument, about 20 minutes after MESSENGER's closest approach to Mercury (2:04 pm EST), when the spacecraft was at a distance of about 5,000 kilometers (about 3,100 miles). The image shows features as small as 400 meters (0.25 miles) in size and is about 370 kilometers (230 miles) across. The image shows part of a large, fresh crater with secondary crater chains located near Mercury's equator on the side of the planet newly imaged by MESSENGER. Large, flat-floored craters often have terraced rims from post-impact collapse of their newly formed walls. The hundreds of secondary impactors that are excavated from the planet's surface by the incoming object create long, linear crater chains radial to the main crater. These chains, in addition to the rest of the ejecta blanket, create the complicated, hilly terrain surrounding the primary crater.  

Keywords for this photo:

2008 - ASTRONOMY - BLACK AND WHITE - CRATER - IMPACT CRATER - MERCURY - MESSENGER - PLANET -