On 15 February 2013, asteroid 2012 DA14 will pass within 22,500 kilometers of the Earth. Geostationary satellites orbit 35,800 kilometers above the surface.
This asteroid is roughly the same size as the object that burst over Tunguska Siberia in 1908.
Our friends at The Planetary Society provided the funds that allowed La Sagra Observatory in southern Spain to upgrade one of their telescopes with a new camera capable tracking fast moving objects like 2012 DA14, and determining their orbit. The new instrument has found more than ten Near-Earth Objects (NEO), along with a previously unknown comet.
The key to the new discoveries involve fast read-out Charge-Coupled Devices (CCD) and revised image filtering software used with the space-junk tracking program at La Sagra.