Early next week, a large asteroid named 2004 BL86 will fly past the Earth-Moon system. There’s no danger of a collision
A large asteroid is about to fly past Earth. On the night of Jan. 26-27, mountain-sized space rock 2004 BL86 will be only 3 times farther from us than the Moon. There’s no danger of a collision, but the flyby will be easy to observe. Sunlight reflected from the surface of 2004 BL86 will make it glow like a 9th magnitude star. Amateur astronomers with even small backyard telescopes will be able to see it zipping among the stars of the constellation Cancer
NASA radars will be observing, too. As the asteroid passes by, astronomers will use the Deep Space Network antenna at Goldstone, California, and the giant Arecibo radar in Puerto Rico to “ping” 2004 BL86, pinpointing the asteroid’s location and tracing its shape.
“When we get our radar data back the day after the flyby, we will have the first detailed images,” said radar astronomer Lance Benner of JPL, the principal investigator for the Goldstone radar observations of the asteroid. “At present, we know almost nothing about this asteroid, so there are bound to be surprises.”
At the moment, astronomers think the asteroid is about a third of a mile (0.5 kilometers) in diameter. The flyby of 2004 BL86 will be the closest by any known space rock this large until asteroid 1999 AN10 flies past Earth in 2027.