This radar image of 1300-foot-wide (400 meter) asteroid 2005 YU55 was obtained on Nov. 7, 2011, at 11:45 a.m. PST (2:45 p.m. EST/1945 UTC), when the space rock was at 3.6 lunar distances, which is about 860,000 miles, or 1.38 million kilometers, from Earth.

This asteroid will pass by Earth tomorrow at 6:28 pm EST, coming within 85% of the distance to the Moon. It’s the closest such pass of an object this large since 1976.

Read more on Discovery News here, and here’s how to view YU55 if you have access to a telescope.

Image credit: NASA/JPL-Caltech