Next week (Feb 15) the earth will be visited by asteroid 2012 DA14 passing inside the gestationary satellite orbits. To quote from http://echo.jpl.nasa.gov/asteroids/2012DA14/2012DA14_planning.html,
2012 DA14 was discovered by the La Sagra Sky Survey in Spain on February 23, 2012. This object will make an extremely close approach to within 0.00023 AU of Earth at 19:25 UT (11:25 AM PST) on February 15, 2013. That is only 0.09 lunar distances or 5.4 Earth radii from the center of the Earth. The close approach will be about 28000 km above Earth's surface. That's inside the distance to geosynchronous satellites but thousands of kilometers above the elevation for low-Earth-orbit spacecraft such as the International Space Station. At the time of closest approach, the asteroid will move about 0.8 degrees per minute.
There is considerable interest in the astronomy community over plans to do radar tracking of the asteroid. The Goldstone 70M dish will be running MAX QRO with 435 kW.
73 de Tom, K3IO