What Factors Determine the Damage of an Asteroid Impact?
The most important factor determining the damage of an asteroid impact is the energy it releases upon impact. This is calculated by multiplying half the asteroid’s mass by the square of its velocity. The typical range of asteroid velocities is quite limited — most measured values are between 12 and 20 km/sec (7.5 – 12.4 mi/sec). Comets are much faster, ranging between 50 and 70 km/sec (31 – 43.5 mi/sec). Yet, what asteroids lack in speed, they make up for in density — while comets are thought to made up of mostly ice, with a density of only 1000 kg/m3, asteroids made of solid rock have a density of about 3000 kg/m3, whereas the rarer (8%) metallic asteroids have a density of 8000 kg/m3. These density values intimately effect the final consequences of the asteroid impact. Other factors influencing the environmental effects of an asteroid impact include its size (obviously), angle of impact (the most probable is 45 degrees), and impact surface (water, silicate rock, or crystalline rock)
