http://www.latimes.com/news/science/sciencenow/la-sci-sn-asteroid-1998-qe2-20130516,0,548201.storyIt's 1.7 miles long. Its surface is covered in a sticky black substance similar to the gunk at the bottom of a barbecue. If it impacted Earth it would probably result in global extinction. Good thing it is just making a flyby.
Asteroid 1998 QE2 will make its closest pass to Earth on May 31 at 1:59 p.m. PDT.