An asteroid capable of sterilizing Earth would not necessarily need to be large; its density and kinetic energy upon impact are critical factors. A football field-sized iron asteroid could potentially eliminate all life, including microbial organisms, depending on its speed and impact dynamics. The discussion highlights that a slow-moving, massive asteroid may leave some life forms intact, while a smaller object traveling at near-light speed could obliterate the planet entirely. Thus, the energy transfer during impact is more significant than the asteroid's size alone.
PREREQUISITESAstronomers, planetary scientists, environmentalists, and anyone interested in the potential catastrophic effects of asteroid impacts on Earth.
threadmark said:For an asteroid to destroy all plants and animals doesn’t have to be big at all. Its density would be the main factor in the final crunch. Depending on how dens and how much contacts the Earth's surface on impact. If you had an asteroid made of iron, a football field sized asteroid would probably do it.
TM
mrspeedybob said:However, a small car traveling at 99.999% of the speed of light would probably transfer enough energy to disintegrate the whole planet. Nothing would survive that.