SCIENCE -- November 8, 2011 at 9:21 AM ET
Asteroid Encounter: YU55 to Fly By Earth on Tuesday
This radar image of asteroid 2005 YU55 was obtained at 2:45 pm ET on Nov. 7 when the space rock was 860,000 miles from Earth. Photo by NASA/JPL-Caltech.
As folks on the East Coast are feeding the dog, cooking spaghetti dinner or watching the NewsHour, an asteroid the size of three Manhattan city blocks will barrel by, missing the Earth by a mere 200,000 miles. That's nearly a sideswipe in astronomical terms.
Scientists and amateur astronomers worldwide will have telescopes trained on Asteroid 2005 YU55 as it flies by at 6:28 pm ET tonight. YU55 is egg-shaped, rich in carbon and believed to be among the most primitive objects remaining since the solar system's planet-forming period some 450 billion years ago, and may hold clues to the origins of life on Earth.
It's the closest an asteroid of this size has been to our planet in 35 years and the closest this particular space rock has been in at least 200 years, according to NASA. But, NASA says, its gravitational influence will have no detectable effect on the Earth's tides or tectonic plates.
This Discovery News article has some tips on how to view the asteroid via telescope.
And Joel Achenbach has determined here, using an asteroid impact calculator from Purdue University, that the if YU55 did smack into Earth, it would leave a crater 2.44 miles in diameter and about 3/4ths of a mile deep. But relax, this one poses no hazard to planet Earth.