Impacts

Energy from the sky

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Impact energy is $\frac12 mv^2$; speeds of tens of km/s make it enormous.
• The Chicxulub impact released about 3 × 10²³ J, 66 million years ago.
• DART (2022) showed that spacecraft can nudge asteroids off course.

Steps

1. The dinosaur killer
2. A megaton rock
3. Planetary defence
4. Exploding in the air
5. A small asteroid
6. A small nudge, early