🗺️ Target Selection - Click the map to aim
Click anywhere to set impact target
Configure, target, and launch. See what happens when space rocks meet Earth - craters, blast waves, seismic shocks and more.
What's inside
Everything you need to explore the science of asteroid impacts - no signup, no downloads, runs in any browser.
Kinetic energy, momentum and crater-scaling equations follow published planetary-impact research. Results are proportional to real-world outcomes.
Click any point on Earth - land, ocean, city - and the simulator calculates impact effects at those exact coordinates, shown as a blast radius overlay.
Iron, stone, carbonaceous and icy cometary bodies have different densities. Composition changes mass, atmospheric survivability and surface energy delivery.
Energy in megatons TNT, crater diameter and depth, fireball radius, thermal radiation zone, air-blast range, seismic magnitude, ejecta range and more.
Adjust impact angle from 15° grazing to 90° vertical. Shallower strikes elongate the blast zone; vertical strikes concentrate maximum energy at a point.
Used by teachers and students to visualise physics concepts, understand planetary defence challenges, and build intuition about scale in the solar system.
Step-by-step
Four steps from blank page to full impact analysis. The whole process takes under a minute.
Use the three sliders to set diameter (10-1,000 m), entry velocity (10-72 km/s) and impact angle (15-90°). Larger, faster, and more vertical means more destructive.
Select iron, stone, ice or carbon from the dropdown. Iron is the densest and most destructive; icy cometary bodies are lighter but can still deliver enormous energy at high speeds.
Click anywhere on the interactive world map. The red pulse marker shows your target. Coordinates update instantly in the panel. You can click a new location at any time.
Press Launch Asteroid. The results panel fills with 10 impact metrics and the map overlay shows the blast zone to scale. Try different settings and compare scenarios.
Asteroid Launcher 2 is a free, browser-based asteroid impact simulator that lets you explore what would happen if a space rock of any realistic size hit Earth. The tool is built for students, educators, science communicators and curious minds who want to understand impact physics without wading through dense academic papers. No account or download is required - open the page and start simulating immediately.
The simulator draws on established cratering mechanics and impact-physics research to compute ten distinct impact effects for each scenario you configure. Results are scaled to real-world observations from events like the Chicxulub impactor (the dinosaur-extinction asteroid), the Tunguska 1908 airburst, and the Chelyabinsk 2013 bolide, so the numbers you see represent meaningful physical quantities - not arbitrary game scores.
Every simulation begins with the four parameters you control: diameter, velocity, impact angle and composition. From these, the calculator derives asteroid mass using the sphere-volume formula and the composition's density (iron: 7,800 kg/m³; stone: 3,000 kg/m³; carbon: 2,000 kg/m³; ice/comet: 1,000 kg/m³). Kinetic energy follows from the classical equation E = ½mv², converted to megatons of TNT for intuitive comparison.
Crater size uses a modified pi-scaling law - the same family of equations used by planetary scientists - adjusted for impactor diameter and impact angle. Thermal radiation and air-blast ranges scale with energy and distance, and seismic magnitude is derived from a log-scale relationship with total ground-coupled energy. Each metric has a clear physical basis, and the results update live on the world map as a blast-radius overlay so you can see scale in geographical context.
The simulator reports ten metrics after each launch. Energy released in megatons of TNT gives a weapons-comparable scale - the Hiroshima atomic bomb released about 0.015 megatons; the Chicxulub impact released approximately 100 million megatons. Crater diameter and depth show the physical scar left in rock. Fireball radius is the zone of immediate thermal incineration. Thermal radiation range marks where exposed skin receives third-degree burns. Air-blast range is where overpressure destroys most structures. Seismic magnitude translates the ground shock to the Richter-like scale familiar from earthquake reporting. Ejecta range shows how far molten or pulverized rock is hurled outward. Together these metrics paint a complete picture of an impact event from ground zero to the horizon.
Teachers and university lecturers use Asteroid Launcher 2 to bring energy and scale concepts to life. Compare the energy of a 50-metre iron asteroid with a nuclear warhead. Show students why the angle of entry changes the blast footprint. Explore why a comet travelling at 72 km/s can outpace a slower iron asteroid many times its size. The tool is suitable for secondary school physics, introductory astronomy courses and public science events. Because all scenarios are explicitly hypothetical, it can be used safely and responsibly in any educational setting.
Common questions
Everything you might want to know about how the simulator works and what the numbers mean.