The image above is an artist's rendition of an asteroid approaching Earth. (Getty Images) On Wednesday, an asteroid almost a mile wide will sail past Earth, coming closer than it ever has within the last 400 years. According to NASA, the , or roughly 683,508 miles, of Earth. It will be one of the strongest asteroid radar targets of this year. The flyby will be the closest of an asteroid of this size since a September 2004 encounter with an...

A meteor streaks across the sky in Vinton, California, during the Perseid meteor shower on Tuesday, Aug. 11, 2009. (AP Photo/Kevin Clifford) The Lyrid meteor shower reaches its peak Friday night into Saturday's pre-dawn hours, when observers can expect to see up to 20 meteors per hour, or roughly one every three minutes.This will be the first meteor shower since January. Although unexpected this year, the Lyrids can sometimes produce as many as 100 meteors in an hour at its...

A security camera captures a fireball streaking across the sky in Cornelius, North Carolina. ...