NASA will play a leading part in protecting the United States and the world from the threat of a dangerous asteroid strike, according to letters sent by John Holdren, director of the White House Office of Science and Technology Policy (OSTP), to Congressional committee leaders on Friday.

Holdren's letters to the Senate Committee on Commerce, Science, and Transportation and the House Committee on Science and Technology assign responsibilities to the US space agency that go beyond its 2005 Congressional mandate to detect and track 90% of potentially hazardous asteroids with a diameter greater than 140 metres. To date the agency has found 903 of the estimated 1,050 asteroids with diameters of a kilometre or more passing within about 50 million kilometres of the Earth.

NASA will be mandated to notify other organizations, including the US Federal Emergency Management Agency (FEMA), if a dangerous asteroid is found, and to drive research and development on the capability needed to deflect the rock.

full article/source - http://www.nature.com/news/2010/101021/full/news.2010.554.html