Monday, December 18, 2006

Tagging Apophis before it tags us.

"A $50,000 (?25,000) competition has been launched to find the best way to tag a 400m-wide asteroid. ... Apophis will come closer to Earth in 2029 than the orbits of many communications satellites - but it will not hit the planet, that is clear. The concern centres on the small chance that its orbit could be perturbed enough in the flyby to put the rock on a collision path for its return in 2036." - bbc

apophis.jpgI'm glad our calculations are good enough to tell for certain that we don't get hit in 2029.
The closest approach of it, being at least 3402,6 km or 2114 miles, would occur the 13th of April 2036 according to the NEO database using analysis based on 2 radar delay, 5 Doppler, and 31 optical observations spanning 884.52 days between 2004-Mar-15.10789 and 2006-Aug-16.626954. There is a 99.99780000% chance the asteroid will miss the Earth. - setiathome

According to one Impact Calculator, if Apophis hit the Earth, you'd hear the air blast as far as 2,000 or 3,000 miles away, but the fireball would be below the horizon and you wouldn't feel the resulting local earthquake. The figures I used were:
Size: 400 meters wide meteor
Density: iron (worst case scenario)
Speed: 17 km/s ( 38,027 miles per hour)
Angle of impact: 45 degrees
Hitting: Ocean ( average depth is 12,175 ft )
Distance from impact: Same as distance of Sacramento, CA from Honolulu, HI, 2458 miles/ 3956 km.

3 comments:

J-dub said...

I used the same Impact Calculator and found out that a 100 yard meteor hitting Reno, NV at "typical impact velocity" would be easily heard and felt in Sacramento, and would send a 5 mi/hr gust of wind and a "fine dusting of ejecta with occasional larger fragments" to the Sacramento area (and visa versa). Oh, and it would leave a 1.3 mile diameter crater. I need to stop calculating impacts before anyone else gets hurt or someone's car gets dented by a meteor fragment...

Mark said...

Send Bruce Willis tbh.

ilushkin said...

OMG! I feel like we all gonna die that day!