Illustration of an asteroid. (NASA/JPL/Caltech) A gigantic "potentially hazardous" asteroid that may be twice the size of the Empire State Building is set to zoom past Earth Thursday (April 28), according to NASA. The asteroid, named 418135 (2008 AG33), has an estimated diameter between 1,150 and 2,560 feet (350 to 780 meters) and will break into Earth's orbit at a blistering 23,300 mph (37,400 km/h). Thankfully, the asteroid is expected to skim past our planet without any risk of impact. At its closest point, the asteroid – traveling at more than 30 times the speed of sound – will come...