Throughout the long history of the Earth, the planet has been struck a number of times by rogue asteroids. I will briefly discuss the effect that such an event could have on the Earth's climate, atmosphere and temperature. A number of problems could arise from such an event, many of which could extend far beyond the immediate strike. The Earth's biosphere could also be significantly impacted by the long-term effects of a meteorite strike. Finally, we will briefly look at the likelihood of future impact, plus some past near misses.
             The effects that an asteroid striking the Earth would have are many and varied and mostly depend on the size of the object impacting the ground. The smallest classification of asteroids, ranging in sizes between 10 to 100 meters in diameter would have little long term affect outside the strike zone. A meteorite of this size could cause damage equal to that of a nuclear explosion and cause massive damage and loss of life if it struck a major population center. An object between 100 meters and 1 kilometer is a greater danger. Even at the smaller end of the scale a strike on land could create a crater 3 kilometers wide as well as eject debris 10 kilometers away. Get close to an object of 1 kilometer wide and the zone of destruction could conceivably cover a small country as well as cause minor damage on a global scale. A strike in the ocean would create large tidal waves which would devastate coastal areas many miles inland. If the same meteorite struck land, the vast amounts of dust thrown into the atmosphere could cool down temperatures on Earth and kill up to tens of millions of people. Finally, the largest scale of asteroids range from 1 to 10 kilometers. The impact from an object of this size could create a crate up to 15 times the diameter of the object itself and cause massive damage even to continental landmasses. Ocean impacts would cause tidal waves never seen before that coul...