Asteroid To Fly-By Earth Could Be Half-Mile Wide | Orbit Animation

Asteroid 2014 HQ124 was discovered on April 23rd, 2014 and its closest approach (~3 Lunar distances) will occur June 8th. Current estimates show it to be between .25 miles - .56 miles wide, and traveling at 31,000 mph.  (Huge Asteroid Webcast Today)

UPDATE June 4th, 2014: NASA/JPL reports that new thermal observations of the asteroid show it to be ~1067 feet-wide (.2 miles)

credit : NASA / JPL