An asteroid has a slight chance of hitting Earth in 2032. Here's why the odds are a moving target, according to the astronomer who invented the scale used to measure such risks.

A recently discovered asteroid, dubbed 2024 YR4, has been making headlines for its ever-increasing chances of striking Earth in 2032. In the past few weeks, the odds of the space rock, estimated to be between 130-300 feet across (big enough to level a city),