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javaguru
Banned
Interesting....
http://en.wikipedia.org/wiki/99942_Apophis
99942 Apophis (previously known by its provisional designation 2004 MN4) is a near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a relatively large probability that it would strike the Earth in 2029. Additional observations provided improved predictions that eliminated the possibility of an impact on Earth or the Moon in 2029. However there remained a possibility that during the 2029 close encounter with Earth, Apophis would pass through a "gravitational keyhole", a precise region in space no more than about 400 meters across, that would set up a future impact on April 13, 2036. This possibility kept the asteroid at Level 1 on the Torino impact hazard scale until August 2006.
Additional observations of the trajectory of Apophis revealed the "keyhole" would likely be missed and on August 5, 2006, Apophis was lowered to a Level 0 on the Torino Scale. As of October 19, 2006 the impact probability for April 13, 2036 is estimated at 1 in 45,000. An additional impact date in 2037 has been identified, however the impact probability for that encounter is 1 in 12.3 million.
Since the odds of impact are known to be very low, the possible effects of an impact are largely irrelevant. However, the initial reports resulted in widespread discussion on many Internet forums, including armchair speculation about exactly where Apophis (then known only as 2004 MN4) would hit and what would happen when it did.
NASA initially estimated the energy that Apophis would have released if it struck Earth as the equivalent of 1480 megatons of TNT. A more refined later NASA estimate was 880 megatons. The impacts which created the Barringer Crater or caused the Tunguska event are estimated to be in the 10-20 megaton range. The 1883 eruption of Krakatoa was the equivalent of roughly 200 megatons.
The exact effects of any impact would have varied based on the asteroid's composition, and the location and angle of impact. Any impact would have been extremely detrimental to an area of thousands of square kilometres, but would have been unlikely to have long-lasting global effects, such as the initiation of an impact winter.
http://en.wikipedia.org/wiki/99942_Apophis
99942 Apophis (previously known by its provisional designation 2004 MN4) is a near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a relatively large probability that it would strike the Earth in 2029. Additional observations provided improved predictions that eliminated the possibility of an impact on Earth or the Moon in 2029. However there remained a possibility that during the 2029 close encounter with Earth, Apophis would pass through a "gravitational keyhole", a precise region in space no more than about 400 meters across, that would set up a future impact on April 13, 2036. This possibility kept the asteroid at Level 1 on the Torino impact hazard scale until August 2006.
Additional observations of the trajectory of Apophis revealed the "keyhole" would likely be missed and on August 5, 2006, Apophis was lowered to a Level 0 on the Torino Scale. As of October 19, 2006 the impact probability for April 13, 2036 is estimated at 1 in 45,000. An additional impact date in 2037 has been identified, however the impact probability for that encounter is 1 in 12.3 million.
Since the odds of impact are known to be very low, the possible effects of an impact are largely irrelevant. However, the initial reports resulted in widespread discussion on many Internet forums, including armchair speculation about exactly where Apophis (then known only as 2004 MN4) would hit and what would happen when it did.
NASA initially estimated the energy that Apophis would have released if it struck Earth as the equivalent of 1480 megatons of TNT. A more refined later NASA estimate was 880 megatons. The impacts which created the Barringer Crater or caused the Tunguska event are estimated to be in the 10-20 megaton range. The 1883 eruption of Krakatoa was the equivalent of roughly 200 megatons.
The exact effects of any impact would have varied based on the asteroid's composition, and the location and angle of impact. Any impact would have been extremely detrimental to an area of thousands of square kilometres, but would have been unlikely to have long-lasting global effects, such as the initiation of an impact winter.
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