What would happen if a massive asteroid enters earth's atmosphere?

Answer 1

Like most other asteroids that do so, it would burn up and simply fall to the ground as fine dust particles. If it were to 'skim' the surface of the atmosphere, it would be pulled slightly towards Earth; at the right speed and height, this would cause it to begin orbiting. Otherwise it is likely to either have its travel affected, and pass through on a path bent from its original one before continuing on, or slow down so much that it began falling directly to Earth (in which case it would either burn up or land and make a small crater or splash). If the asteroid were big enough, even by passing close enough to Earth, it can have an effect on the tides on the surface nearest it; it may also begin orbiting, although this has an extremely low probability.

Answer 2

Then there would be no planets. Asteroids were part of the debri cloud that formed when the sun was being born. While the sun was in its infancy, the asteroids were colliding with each other an merging into larger asteroids till they became so big, they became huge round balls of rock, from which all the inner planets were formed, like Earth. I'm not very sure if the same goes for the gas giants but am certain this occurred for the rocky planets. Now, if what your asking is if the planets are already here and the asteroids were gone, what would happen? The answer is very simple, we wouldn't exist. Asteroids have been a great part in evolutionary history on Earth, for example, if the asteroid that killed dinosaurs didn't exist, then they might still be roaming the Earth and no mammals would exist, like you and me. We owe our existence to asteroids.

Answer 3

It causes huge craters