Newly-discovered asteroid 2012 KT42 is flying past Earth today (May 29th) only about 14,000 km above the planet's surface. This means 2012 KT42 will actually fly inside the Clark Belt of geosynchronous satellites. 2012 KT42 is 3- to 10-meter wide and ranks # 6 on the top 20 list of closest-approachers to Earth. According to the asteroid's orbit, there is no danger of a collision. Even if it did eventually hit Earth, it is too small to cause significant damage. It would likely disintegrate almost entirely in the atmosphere, peppering the ground below with relatively small meteorites.
The asteroid was discovered by A. R. Gibbs in the course of Mt. Lemmon Survey with a 1.5-m reflector + CCD on May 28, 2012 at magnitude ~18.1.
To learn more about 2012 KT42 and the survey which led to its discovery, follow this URL:
To learn more about NASA' Near-Earth Object Program, follow this URL: neo.jpl.nasa.gov