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Universe Sandbox Apr 2026

You can even create a "Tiny System" by shrinking a star down to the size of a flashlight while keeping it hot enough to support life. 2. Build the Worlds (Planetary Composition)

Adjust the axial tilt to create extreme seasons or "tidally lock" a planet so one side is always burning and the other is always frozen. 3. Add the Details (Moons, Rings, and Life) universe sandbox

In the , planets aren't just static spheres; they are made of 12 distinct materials , including iron, silicate, water, and hydrogen. You can even create a "Tiny System" by

Once your planets are in orbit, you can flesh out their history. Every cosmic story needs a center

Every cosmic story needs a center. You can begin by adding a to an empty simulation.

Here is how you can put together a story using the tools available in the simulation: 1. Set the Stage (The Star)

Will it be a stable yellow dwarf like our Sun, or a volatile blue giant ?