# Calculate the Energy of an Asteroid Impact

Calculator for the approximate energy released when an asteroid or meteorite hits. This energy is the kinetic energy of the asteroid, which is completely transferred to Earth or the site of impact. The formula for the calculation is _{kin} = m * v² / 2

The mass of an asteroid is often not known, but has to be estimated. This is difficult because asteroids are usually not spherical. The estimation is done here using the average diameter, the formula for the estimated volume is

Also the density can often only be estimated, here an average density is preset. However, the density of asteroids has a large spread. A typical speed of asteroids on impact is about 50000 km/h, also with large spread.

Please enter the average diameter or the mass and the speed. The energy is calculated in (kilo-, mega-, giga,-, ...)joules and as TNT equivalent.

Example: Asteroid 2043 DW, which will approach Earth in February 2046, has an average diameter of 50 meters. Its estimated mass is 163.6 kilotons (kt). That would release 15.78 petajoules (PJ, 10^{15}J) in a collision, which is equivalent to 3.77 megatons (Mt) of TNT.

German: Planeten-Rechner