WHAT WOULD HAPPEN IF A MASSIVE OORT CLOUD COMET STIKES EARTH?
Long period comets originate in the Oort Cloud, a huge sphere comprising trillions of comets that surrounds the solar system, 20,000 to 100,000 Astronomical Units (AU) from the Sun. Long period comets will often return after thousands or even millions of years, or not at all. The Oort Cloud is estimated to contain 7,000,000,000,000 comets. There are 5 to 10 long period comets that approach the Sun each year. Some of these comets are behemoths, which are several hundred miles across. What would happen if a massive Oort Cloud comet struck the Earth? The impactor would smash through the planets crust and drive deep into the planets interior where it would release most of its energy. A large comet, 200 miles in diameter, traveling at 100,000 mph with a density of 0.75 gm/cc would have impact kinetic energy equivalent to 3.1 x 1012 megatons of TNT. The kinetic energy from the Cretaceous/Tertiary (K/T) impact of 65 millions years ago, that caused the extinction of many lifeforms including di
