Huge asteroid hitting the Earth - What would happen?

A huge asteroid hitting the Earth was main theme of many Sci-Fi movies, and both the filmmakers as well the scientists agree that such hit would cause enormous disaster on our planet. The last time huge asteroid hit the Earth it killed the dinosaurs, the largest creatures ever on land, and if such scenario would to happen again it would again destroy many species on our planet.

Gregory L. Matloff, NASA researcher and New York City College of Technology, has for many years researched the possible impacts of asteroids hitting our planet, and most notably the best ways to avoid such a scenario. He believes that the best solution to avoid such scenario is to change the trajectory of the asteroid or in alternate case to destroy it.

In not so far future or to be more precise in 2029 and 2036, the asteroid called Apophis (named appropriately after the Egyptian god of darkness), having at least 1,100 feet in diameter, 90 stories tall, and weighing an estimated 25 million tons, will make two close passes by Earth at a distance of about 22,600 miles.

The impact of this asteroid (traveling at an estimated 30,000 to 40,000 miles) hitting the earth would cause total disaster, in fact it would strike our planet with 68,000 times the force of the atom bomb that leveled Hiroshima.

Many scientists agree that the potential impact with Apophis is very unlikely but even avoiding the impact itself doesn't exactly free us of danger because there is a possibility that when Apophis passes in 2029, heating as it approaches the sun, it could fragment or emit a tail, which would act like a rocket, unpredictably changing its course. Scientists also warn that if Apophis or its remnants enter one of two "keyholes" in space, impact might happen when it returns in 2036.

The best way to avoid impact with such objects is to try to change their trajectory though some would no doubt prefer the method of "lets blast em". The latter method could result in a radioactive shower from the debris, and this is certainly something we wouldn't like to see.

But how to change the trajectory of asteroid? Dr Matloff explains that this can be done by heating its surface to create a jet stream, which would alter its trajectory, causing it to veer off course. In theory this could be done with the help of a solar collector (SC), which is a two-sail solar sail configured to perform as a concentrator of sunlight.