The expected number of celestial bodies that will impact this planet in 10 years is the integral of the product of the possible direction along with the probability density function; in essence the sum of the total objects over all possible directions. If the answer is more than one, we will have less chance of survival. We want the probability to be low because we are adding for infinitely possible directions. Then again, catastrophe theory may be fear mongering or a public anxiolytic.
