"The asteroid, referred to as 2012 DA14, has a diameter of approximately 45m and an estimated mass of 130,000 tonnes.
It was discovered at the start of 2012 and is set to travel between the Earth and our geostationary communication satellites on
15 February 2013.
At a distance of just 22,500km this will be the closest asteroid ‘fly by’ in recorded history."
http://www.cosmosmagazine.com/news/6...ory-pass-earth
On this date, the asteroid will travel rapidly from the southern evening sky into the northern morning sky with its closest Earth approach occurring about 19:26 UTC when it will achieve a magnitude of less than seven..
http://neo.jpl.nasa.gov/news/news174.html