The Impact of a 100 Meter Asteroid Could Kill Many

question 8

Multiple Choice

The impact of a 100 meter asteroid could kill many people if it struck a major city. Suppose the probability of such an impact in any single year is 1 in 1,000, and suppose we know (somehow) that it has been 1200 years since the last impact. What would that tell us?

• A)Nothing, we would still presume that the chance of such an impact during the next year is 1 in 1000.
• B)The prediction must be wrong, since the time since the last impact has been 1200 years.
• C)We are overdue for such an impact, so we should expect to be hit by something even larger during the next few years.
• D)We are now due for such an impact, so the actual probability for the coming year must be much higher than 1 in 1000.