NASA's Dawn spacecraft completed its higher altitude mapping and has been lowered to about 130 miles. This will provide higher resolution photos and greater details on areas that were mapped at the higher altitude. The lower altitude will also allow for mapping of the gravitational field of the 2nd largest asteroid in the solar system which then allows for a greater understanding of the internal structure of the mini-world.
The maneuver was done successfully on December 12 and Dawn will remain at this altitude for the next 10 weeks. She will then dive back up to the higher altitude of 420 miles to resume mapping of the northern regions with a more favorable Sun alignment. Dawn will head for the largest asteroid Ceres in July 2012.
Read More ABout it: http://www.jpl.nasa.gov/news/news.cfm?release=2011-384
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