An asteroid the size of the Empire State Building flew past Earth in early February, coming within 1.8 million km (1.1 million miles) of our planet. Not only is it approximately the same size as the building, but astronomers found the asteroid – named 2011 AG5 — has an unusual shape, with about the same … Continue reading A 500-Meter-Long Asteroid Flew Past Earth, and Astronomers Were Watching