Prepare for Impact

[url=http://news.discovery.com/space/asteroid-2011-md-near-miss-monday-110624...! Asteroid to Narrowly Miss Earth on Monday[/url]

Quote:

This may sound like late notice, but astronomers have just spotted a rather chunky asteroid heading our way, set to narrowly miss us on Monday.

In fact, it will be such a narrow miss that astronomers in the Southern Hemisphere should be able to spot the flyby with fairly modest telescopes.

[url=http://news.discovery.com/space/visualizing-asteroid-2011-md-zip-past-ea... asteroid will come closer to Earth than the orbits of the GPS satellites.[/url]

The 600-tonne asteroid made its closest pass of earth this morning [June 27]. If you had been standing under it, it would have been closer to you than the other side of the Earth is.

[url=http://www.wired.com/wiredscience/2011/06/close-asteroid/]Photos here[/url]

ETA:

Never before this has an asteroid passed at a distance of less than a few Earth radii [b]and[/b] been observed both before and after the encounter. Scientists noticed that the path of the asteroid as it moved away was slightly different than they had predicted with their calculations. Turns out they had not allowed for the fact that Earth is not a perfect sphere, which threw their gravitational calculations off slightly. Normally it wouldn't make a difference, but with encounters as close as this one, it does. Scientists have now amended the way they do their predictions of the orbital paths of closely-approaching objects.

Which is a good thing.

More ETA:

You can view an [url=http://www.youtube.com/user/majikthyze42#p/a/u/0/5EXbPDK0tbQ]amazing YouTube video[/url] of the asteroid flyby made by a Canadian astronomer. Each frame of the video represents 2 seconds, so the effect is speeded up. You can actually see the brightness of the asteroid fluctuate as it tumbles through space and the reflectivity of its surface changes in a regular pattern.