1. Asteroid Impact
A massive asteroid impact remains one of the most well-known existential threats to our planet. Roughly 66 million years ago, the Chicxulub asteroid struck Earth, triggering the mass extinction that wiped out the dinosaurs. Today, scientists vigilantly monitor the skies for similar threats. Through initiatives like NASA’s Planetary Defense Coordination Office, humanity is developing ways to detect and potentially deflect hazardous near-Earth objects before they spell disaster.