Asteroid as Large as the Golden Gate Bridge Approaching Earth

WASHINGTON — This year's second-largest "potentially hazardous" near-Earth object is incoming at speeds of over 11,000 kilometers per second and will zoom past our planet on May 21.

Asteroid 136796, also known as 1997 BQ, is estimated by NASA to be between 640 meters and 1.4 kilometers wide, or roughly the size of the Golden Gate Bridge.

1997 BQ orbits our Sun every 844 days.

According to NASA's Asteroid Watch, on May 21 it will pass Earth at a distance of 6.2 million kilometers, slightly closer than this year's largest potentially hazardous near-Earth object, 1998 OR2, which flew past Earth on April 29 at a distance of 6.3 million kilometers.

NASA classifies a near-Earth object — either a comet or an asteroid — as a potentially hazardous object if its orbit brings it within 7.5 million kilometers of Earth's orbit and it is greater than 140 meters in size.

According to NASA's Center for Near-Earth Object Studies, as of April 21, some 22,582 near-Earth objects had been discovered.

Of these, 9,085 were 140 meters or larger in size, and 902 were estimated to be larger than one kilometer.

By comparison, the Chicxulub asteroid that wiped out the dinosaurs is estimated to have been 11 to 81 kilometres in diameter.