Earth having a bad day....

Energy, Effects & Average Rates of Impact 
stony meteor of given diameter, impact speed = 20 km/s

Diameter (km) Event Energy (TNT) Quake (M) Crater (km) Est. Avg. Rate: 1 per
0.001 fire ball       6 days
0.003 fire ball       2.8 months
0.01 air burst 59.5 kilotons     4.1 years
0.03 air burst 1.61 megatons     58 years
0.1 impact 59.5 megatons 6.8 1.3 x 0.2 1,000 years
0.3 impact 1,610 megatons 7.7 3.8 x 0.4 14,000 years
1 impact 59,500 megatons 8.8 12.5 x 0.6 260,000 years
3 impact 1.61 million megatons 9.8 37.1 x 0.9 3.6 million yrs
10 impact 59.5 million megatons 10.8 122 x 1.2 66 million yrs
30 impact 1.61 billion megatons 11.8 327 x 1.7 920 million yrs
100 impact 59.5 billion megatons 12.8 847 x 2.2 few billion yrs
Color code scale of destruction:  
blue pretty sight, no destruction  

green localized destruction, death  

orange local to regional destruction, death  

red hemispheric destruction, death  

black global destruction, death      
Energy released in past events:      
Hiroshima atomic bomb (1945) 13 kilotons TNT
Bikini Atoll H-bomb "Bravo" (1954) 15 megatons TNT
Tunguska air burst (1908) 15 megatons TNT
Barringer Crater, AZ (49,000 BP) 49 megatons TNT
large fragment of SL-9 Jupiter (1994) 5 million megatons TNT
Chicxulub (65 million BP) 100 million megatons TNT
Numbers and destructive effects presented here are approximate, and depend upon details such as impact speed, composition of impactor, impact site (land, ice sheet,or ocean), and other factors. Not all of the kinetic energy is available upon impact (or even released all at once), but the fraction that is grows initially with the mass of the impactor. Threshold for significant global climate effects probably lies near the 1-3 km impactors. Of the information presented in the table, the impact rates, especially for the larger objects, have the largest uncertainties. Some of the information presented here has its origins in Doug Hamilton's Solar System Collisions web page. This web site takes the user's choice of parameters governing the impact, computes all of the effects in great detail, and presents these in a table. A "neat" plot is shown here. Finally, links to more information may be found here.

Last Updated on 28 September 2004
By Kirk T. Korista