NASA says an asteroid about a third of a mile wide (500 meters wide) known as 2004 BL86 will pass within 745,000 miles (1.2 million kilometers) of Earth on Jan. 26. The space rock should be big enough and close enough for amateurs to spot using a small telescope or a powerful pair of binoculars — but it won't pose any risk to Earth in the foreseeable future, NASA's Jet Propulsion Laboratory says.
"I may grab my favorite binoculars and give it a shot myself," Donald Yeomans, who is retiring as manager of NASA's Near Earth Object Program Office at JPL, said in a Tuesday news release.
The asteroid was discovered 11 years ago, but this month it's coming as close to Earth as it will get for at least the next 200 years, Yeomans said. 2004 BL86's flyby will be the closest pass by any known space rock this large until 1999 AN10's close encounter in 2027, according to NASA. (For what it's worth, a much smaller asteroid called 2014 RC came much closer to Earth last September.)
The Jan. 26 flyby will be closely watched by NASA scientists as well as amateurs. For tips on how to spot the asteroid, check out EarthSky's viewing guide.