An asteroid that was discovered only four days before it flew by the Earth on June 14 has turned out to be much bigger than first thought.

An asteroid that was discovered only four days before it flew by the Earth on June 14 has turned out to be much bigger than first thought.

This particular asteroid may not have been a danger, but much of the concern was rooted in the late warning of its detection — 2012 LZ1 was spotted only four days before closest approach. One of the reasons for its late discovery is because it was detected in Southern Hemisphere skies, part of the world were we have few asteroid-watching programs. If it had been on a collision course with Earth, a few days notice is no time at all.

So, in the aftermath of the flyby, astronomers at the famous Arecibo Observatory in Puerto Rico used radar to image the interplanetary interloper (pictured top). What they uncovered was a surprise: Asteroid 2012 LZ1 is actually bigger than thought… in fact, it is quite a lot bigger. 2012 LZ1 is one kilometer wide (0.62 miles), double the initial estimate.