writes "There have been numerous discussions on /. regarding the matter of a large asteroid hitting the Earth, its consequences and how to avoid such a catastrophe. Now, researchers from the University of Arizona and Imperial College London have produced a software that lets you have a free swing at the Earth by the impactor of your choice. They have a nice web interface that makes creating doomsday scenarios a snap.
Just type in a few variables such as diameter, density, and velocity and Impact: Earth! will send a comet or asteroid hurtling toward our planet. Lest you be unsatisfied with a simulation of a massive rock barreling down on us, the Web site also provides data on the aftermath, including the size of the crater, the extent of the fireball, and even the height of the tsunami wave, should the object crash into the ocean.
Details on the calculations can be found in a paper published by the researchers."
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