Planets in a Box
Crash planets together, from grazing hits to head-on impacts.
A real-time simulator of planetary collisions. Every planet is made of tens of thousands of particles of rock and iron that pull on each other with gravity, collide, heat up and splash. Watch a young Earth get hit by a Mars-sized body, see molten debris spread into a disk, and a new moon gather in orbit.
Screenshots
Click to enlarge
What you can do
Recreate the Moon-forming impact
Start with the classic giant impact: a Mars-sized planet strikes the early Earth at an angle. Follow the impact, the glowing debris and the disk that forms around the planet afterwards.
Try your own collisions
Choose a grazing hit-and-run, a head-on impact, or a cold, rotating dust cloud collapsing into a planet with clumps in orbit. Change the masses, impact angle, speed, core size and spin before you start.
Build your own system
Start from empty space and add planets, the Moon or bodies of your own. Put them in orbit, give them a push or a spin, or shoot one at a planet.
Look inside
Cut the planets open with a section plane to see the iron core and the mantle. Colour the material by type, temperature or density, or show realistic planet textures. Select any clump to see its mass, speed and spin, and drag the arrows to change them.
Control time
Pause, rewind the last moments, and speed the simulation up or slow it down. Choose how many particles to use, to balance detail against speed.
Record and replay
Record a run and replay it later from any angle, or save it as a video.
How it works
Planets in a Box uses smoothed particle hydrodynamics (SPH) with self-gravity, running entirely on your device's graphics processor. Rock and iron follow simplified equations of state, so planets compress, heat up and flow.
The physics is simplified so it can run in real time. It is meant for exploring and learning rather than research, and the results depend on the number of particles and the model assumptions.
- ReleaseComing soon
- OfflineWorks offline
- ProAn optional upgrade adds building your own system, scenario options and editing speed and spin.
- RequirementsA device with Vulkan graphics. Performance and particle count depend on the device.
- PrivacyNo ads, no account, no data collected. Privacy policy
