Small Asteroid Predicted to Cause Brilliant Fireball over Northern Sudan (2008 TC3)

From Nasa/JPL

http://neo.jpl.nasa.gov/news/news159.html

A very small, few-meter sized asteroid, designated 2008 TC3, was found Monday morning by the Catalina Sky Survey, (the Siding Spring Survey is the Southern partner in this endeavour) from their observatory near Tucson Arizona. Preliminary orbital computations by the Minor Planet Center suggested an atmospheric entry of this object within a day of discovery. This object, with the survey-assigned designation 8TA9D69, was discovered by the University of Arizona Mt. Lemmon survey and will almost certainly, tonight, become the first impacting bolide discovered before entry into the Earth’s atmosphere.

JPL confirmed that an atmospheric impact will very likely occur during early morning twilight over northern Sudan, north-eastern Africa, at 2:46 UT Tuesday morning which is 13:46 local time here in NSW Autralia. The fireball, which could be brilliant, will travel west to east (from azimuth = 281 degrees) at a relative atmospheric impact velocity of 12.8 km/s and arrive at a very low angle (19 degrees) to the local horizon. It is very unlikely that any sizable fragments will survive passage through the Earth's atmosphere.

Based on 26 optical observations from 2008/10/06.278 to 2008/10/06, the probability of impact is between 99.8% and 100%; in practice the impact can be considered sure and is for tonight. 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.

Just to allay the fears of anyone who might panic: A few dozen meteoroids between 1 and 10 meters diameter are confirmed to enter Earth's atmosphere annually, with the actual number being perhaps an order of magnitude greater. What makes this interesting is that this is the first time such an event has been predicted ahead of time and it reflects the increasing capability of the Spaceguard Survey.

See you can all sleep tight at night knowing the team on the NEO survey both here at SSO and up there in the North are on the job!

Spaceweather.com has only an hour ago reported that the 3 metre diameter asteroid 2008TC3 hit the earth’s atmosphere over the Sudan. Impact speed was calculated to be about 12 km per second which is fairly slow.