Record-setting "near miss" of Earth dramatically shifted tiny asteroid's orbit

Record-setting "near miss" of Earth dramatically shifted tiny asteroid's orbit

The solar system is littered with natural debris—asteroids, comets and pieces of the same that occasionally wind up in the steamrolling path of one of the planets. When a piece of debris encounters the friction of Earth's atmosphere, it flares up as a meteor, or shooting star, and pieces of the object may survive the heat of reentry to reach the surface as meteorites.

Many more objects whiz past Earth without striking the atmosphere, perhaps returning for another pass some years later. Many of those go undetected, especially the small asteroids that are harder to spot with the relatively modest telescopes that keep watch for near-Earth objects.

But sky monitors did spot one small asteroid, called 2011 CQ1, less than a day before it buzzed Earth at the smallest distance ever recorded. On February 4, the meter-size rock flew over the Pacific at an altitude of about 5,500 kilometers—about one-seventieth the distance between Earth and the moon and well below the orbit of some high-flying satellites.

But even though 2011 CQ1 skirted immolation in Earth's atmosphere, it did not escape from the encounter unmolested. Earth's gravity gave the asteroid a good tweak, redirecting its trajectory by about 60 degrees in much the same way that interplanetary spacecraft use the gravity of the planets for course corrections or speed adjustments. "Prior to the Earth close approach, this object was in a so-called Apollo-class orbit that was mostly outside the Earth's orbit," asteroid trackers Don Yeomans and Paul Chodas wrote on the NASA Near-Earth Object Program Web site. "Following the close approach, the Earth's gravitational attraction modified the object's orbit to an Aten-class orbit where the asteroid spends almost all of its time inside the Earth's orbit."

More:
http://www.scientificamerican.com/blog/post.cfm?id=record-setting-near-miss-of-earth-d-2011-02-10&

Very interesting snip. Thanks.

I bet if you search the Google News you could find more, I'll do that now!

Shouldn't it be a 'near hit?' It's not a 'near miss' -- it's a full-fledged 'miss.'

"Oh look, those two airplanes nearly missed!"

Cool link! Thanks!

This, my friends, is why we need some kind of literal space based defense system, to break this shit up before it gets close to Earth. People just don't treat this like it's a real concern.

Just look how little the amount of time was they had as a warning!

And they can't follow it's path and compute a new orbit that fast? Why is that Orbiter space simulator can do it real time on a desktop computer, and come up with a moderately accurate simulation? That's a bunch crap.

I'm sorry to be so profane, that is my style in GD, but usually for Science I'm a tad more reserved, but this is a big deal. There is simply not enough money being given to this problem.

Perhaps Orbiter can simulate orbits because you first define the exact parameters of an object, and then get it to say where it would expect such an object to go. You don't start by giving it uncertain data got by trying to see a metre-wide object (just in reflected sunlight) many thousands of kilometres away, coming almost directly at you, and then have to base your estimate of its position and velocity on what observations you can make (which is only the direction of its position - unless you can pick it up on a radio telescope).

If you have Orbiter installed, I'd be interested to know how much difference to something going through a slingshot some uncertainty in the initial position and velocity makes - especially when it's not just the initial direction away from Earth that's wanted, but the long term orbit around the Sun.