What Happens When It Hits?
Configure your asteroid and watch the destruction unfold.
The Asteroid Impact Simulator is a free online tool that lets you configure an asteroid's size, speed, composition, and impact angle, then visualize the destruction it would cause. The simulator calculates realistic crater dimensions, shockwave effects, fireball radius, earthquake magnitude, and long-term climate consequences. The Chicxulub asteroid that killed the dinosaurs 66 million years ago was roughly 12km wide and released energy equivalent to 10 billion Hiroshima bombs.
Adjust four sliders to configure your asteroid: diameter (10m to 500km), velocity (11-72 km/s), composition (ice, rock, or iron), and impact angle (15-90 degrees). Or use preset scenarios like the Chelyabinsk meteor or the Chicxulub dinosaur killer. Hit "Launch" to watch the impact animation, then scroll through detailed results cards showing the crater, shockwave, fireball, and global effects.
Effects depend on size: a 10m asteroid creates a bright fireball, a 1km asteroid devastates a country-sized area and affects climate, and a 10km+ asteroid causes mass extinction through firestorms, tsunamis, and years of blocked sunlight.
The Chicxulub asteroid was approximately 10-12 kilometers wide. It struck Mexico's Yucatan Peninsula at roughly 20 km/s, releasing energy equivalent to 10 billion Hiroshima bombs and creating a 180km-wide crater.
Humanity could likely survive impacts from asteroids under 1km. Asteroids over 10km would trigger mass extinction. NASA's DART mission in 2022 successfully demonstrated asteroid deflection, providing hope for preventing future impacts.
If you enjoyed this, try these: Nuclear Simulation · Size of Space · Center of Earth · Earth in a Day
Last updated: March 2026 · whatifs.fun — Free interactive games, experiments & simulations