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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 YaoDina Freedman10.25.11
Frequency: graph
MeteoritesVelocity: typically 10 to 70 km/s when entering atmosphere
Large
SmallSlow 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/ 3.1536 * 10⁷ s
• Power=1.92*10⁸ W or 1.92 *10⁵ kW
• An average house uses 1.8 kW
50m 250m 500m 2500m 5000m0.00E+00
2.00E+06
4.00E+06
6.00E+06
8.00E+06
1.00E+07
1.20E+07
Diameter and Energy
Diameter of the meteorites
Ener
gy in
meg
aton
s of
TN
T
1.3E+06 megatons
1.1E+07 megatons
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
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