Meteor / Asteroid Impact Energy Calculator
Calculate the kinetic energy of a meteor or asteroid impact in megatons TNT.
Enter size, density, and impact speed.
Compare to famous impacts.
Impact Energy
Asteroid and meteor impacts release enormous amounts of kinetic energy upon collision.
Mass from diameter:
Volume = (4/3) × π × (d/2)³ (assuming spherical body)
Mass = ρ × Volume
Kinetic energy:
KE = ½ × m × v²
Converting to megatons TNT:
1 megaton TNT = 4.184 × 10¹⁵ joules
Typical impact velocities:
- Near-Earth asteroid average: ~20 km/s
- Comets: 20–70 km/s
- Maximum (head-on comet): ~72 km/s
Famous impacts for scale:
| Event | Size | Energy | Effect |
|---|---|---|---|
| Tunguska, Siberia (1908) | ~50 m stony | ~10–15 MT | Flattened 2,000 km² of forest |
| Chelyabinsk, Russia (2013) | ~20 m | ~500 kt | Injured 1,500 people, shockwave damage |
| Barringer Crater, Arizona | ~50 m iron | ~10 MT | 1.2 km diameter crater |
| Chicxulub (K-Pg boundary) | ~10–15 km | ~10⁸ MT | Mass extinction (dinosaurs) |
| Largest nuclear bomb (Tsar Bomba) | — | 50 MT | For comparison |
Common densities:
- Stony (chondrite): ~3,000 kg/m³
- Iron meteorite: ~7,800 kg/m³
- Cometary nucleus (icy): ~500–1,000 kg/m³
- Carbonaceous chondrite: ~1,500 kg/m³