A mountainous asteroid will make a near-Earth pass Monday night, giving us a preview of an event that could have our descendants sweating.
Asteroid 2004 BL86, about five football fields wide, will come within 745,000 miles of Earth -- about three times as far away as the moon -- at a rate of 35,000 mph.
"It's passing safely by Earth," says Paul Chodas, the new head of NASA's Near Earth Objects program office at JPL.
"It's worth keeping an eye on in future centuries," he noted, but this particular asteroid won't pose a threat of hitting Earth "for hundreds of years."
What has scientists at Pasadena's Jet Propulsion Laboratory excited are the pictures they are set to snap of the space rock.
"It's coming so close, we can use radar to get an image of it," Chodas said, "and the images should be spectacular. I'm really looking forward to them."
You may be able to glimpse 2004 BL86 with strong binoculars or a telescope.
Ed Krupp, astronomer and director of Griffith Observatory in Los Angeles, cautions the asteroid passage will be a "subtle event" -- unlike the fly-by of Comet Lovejoy, "it's a much greater challenge to detect an asteroid moving like that."
Timing and a star chart are crucial, he noted.
The observatory is closed Mondays, so telescopes on the lawn won't be trained on the skies for asteroid detection. But "experienced amateur astronomers" have a good chance of seeing BL86, Chodas said.
"It will not be too far from Jupiter, which is very bright in the sky," he said, "and rising as soon as it gets dark."
The asteroid should be highest in the sky at midnight, he said, and observers should look for the thing that "doesn't belong."
"The star that shouldn't be there. That's the asteroid. In a telescope, you might be able to see it moving."