Impacts of Meteors Meteor: Glowing fragments from outside the atmosphere that burn upon entry Meteorite: Piece of rock that strikes earth from space Asteroid: Small solar system bodies orbiting around the sun Yao Dina Freedman
Frequency: graph Meteorites Velocity: typically 10 to 70 km/s when entering atmosphere Large Small Slow down to “almost nothing”, same velocity as an object dropped from a plane Reach the ground with high velocity, result in a crater Nelson, 2010
Kinetic Energy and Power Meteorite Flux =10⁷- 10⁹ kg/year Escape Velocity= 11 km/s KE = ½ * 10⁸kg * (1.1*10⁴ m/s)² =6.05 * 10¹⁵ Joules Power = 6.05 * 10¹⁵ Joules/ * 10⁷ s Power=1.92*10⁸ W or 1.92 *10⁵ kW An average house uses 1.8 kW
10 megatons 0.1 megatons
Historical Impacts The KT extinction 65 MYA created the Chicxulub Crater about 180 km in diameter The 1908 Tunguksa Siberia meteor knocked down trees for about 850 sq. miles but did not leave a crater