Category Archives: spaceguard survey

Asteroid Piece on Course for Earth

No Damage Expected and It’s Not a Threat

As reported on Phil Plait’s Bad Astronomy site and through the Minor Planets Center at the Harvard-Smithsonian Center for Astrophysics, an object called 2008 TC3 is going to enter Earth’s atmosphere tonight and burn up over Sudan.  It’s very small–only about 2 meters across–which means that by the time it gets through our atmosphere, only a few small rocks will be left to rain down on the desert (if any of it is left to fall). The entry time, as reported by Steve Chesley of NASA JPL is 2:45 UT October 7 (equivalent to 10:46 p.m. Eastern time in the U.S.).  For folks along the path of entry, it should be a great bolide to watch as it streaks in from space!

So, the amazing thing about this predicted impact is NOT that it is going to occur, although that’s pretty neat. It’s not even that it’s a piece of space rock coming in — although it should be pretty darned spectacular to see!  No, the coolest thing about this whole thing is that this is the first time an incoming asteroid and potential impact has ever been predicted. The sightings of this thing have been coming in from the SpaceGuard Survey over the past half day and they are good enough to predict the time of the object’s entry into our atmosphere. It’s pretty amazing that the survey has been able to spot something this small.

Now, in case you’ve seen some woo-woo reports about this thing, it’s not anything more than an incoming rock from space. There’s lots of them out there, and given enough time, we’re bound to see one or two of this size come in every once in a while.  There’s nothing magical or mystical about it. It’s all quite natural.

Of course, questions are arising about its possible effect on Earth. According to Andrea Milani at the University of Pisa,

“the effect of this atmospheric impact will be the release, in either a single shot or maybe a sequence of explosions, of about 1 kiloton of energy. This means that the damage on the ground is expected to be zero. The location of these explosions is not easy to predict due to the  atmospheric braking effects. The only concern is that they might be  interpreted as something else, that is man-made explosions. Thus in  this case, the earlier the public worldwide is aware that this is a  natural phenomenon, which involves no risk, the better.”

Folks who track these things for a living are hoping that scientists will be able to mobilize some spectrographs and cameras to do some in-depth studies of the object as it comes in.  Such studies will help astronomers figure out the shape and chemical composition of the naturally occurring rocks it was made of, and help determine where it first formed in the solar system some 4.5 billion years ago.

The meteor should be visible from eastern Africa. It will likely appear as an extremely bright fireball traveling rapidly across the sky from northeast to southwest. It should enter the atmosphere over northern Sudan at a shallow angle.

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