A small shift in trajectory has raised the risk of a lunar impact — but the scariest part is, we can't track it anymore.

YR4 holds a 4 per cent chance of hitting the Moon. Discovered after it had already passed Earth, the asteroid's trajectory highlights the limitations of current Earth-based detection systems.

Initial sightings of Asteroid 2032 YR4 were tricky, but tracking has gotten better, helping us understand its path. New data, ...