If you get asteroids about a kilometer in size, those are large enough and carry enough energy into our system to disrupt transportation, communication, the food chains, and that can be a really bad day on Earth.
Neil deGrasse Tyson... there is no shame in not knowing. The problem arises when irrational thought and attendant behavior fill the vacuum left by ignorance.
Neil deGrasse TysonI suppose I can live with missing decimals, missing floors to tall buildings, and floors that are named instead of numbered. A more serious problem is the limited capacity of the human mind to grasp the relative magnitudes of large numbers. Counting at the rate of one number per second...to count to a trillion takes 32,000 years, which is as much time as has elapsed since people first drew on cave walls.
Neil deGrasse Tyson