Gravity Lab

About Gravity Lab

A free 3D model of the real universe that runs in your browser, with real physics you can experiment with.

Gravity Lab lets you fly from low Earth orbit to the edge of the observable universe without a loading screen in between. You start above the Earth. From there you can follow the International Space Station, drop through the clouds of Venus, catch up with Voyager 1 in interstellar space, visit the stars that host known exoplanets, and keep going past the Milky Way to Andromeda and beyond. Everything is where it really is today: planets and moons ride their real orbits, spacecraft follow their real trajectories, and the clock runs at real time until you speed it up.

Then you can break it. Sandbox Mode switches the Solar System from fixed orbits to live gravity, where everything pulls on everything else. Throw an asteroid at the Earth, drop a black hole next to the Sun, light Jupiter up as a star or collide two galaxies, and the physics decides what happens next.

Open Gravity Lab

What you can do

Explore the real universeThe Sun, planets, moons, dwarf planets, comets, spacecraft, stars, nebulae and galaxies, at their real positions. Experiment with gravityAdd, throw, grab and explode anything in Sandbox Mode, and watch Newtonian gravity play it out. See a black holeRay-traced black holes, with the bent accretion disk, photon ring and lensed starlight. Collide galaxiesWatch the Milky Way and Andromeda merge, and see where the Sun ends up. Simulate impactsCrater size, blast and heat for anything that hits Earth, from Tunguska to the dinosaur killer. Test wild ideasThe Theory Lab checks warp drives, wormholes and time travel against real physics.

Why it exists

Pictures of space are beautiful, but they hide the scale. Images and diagrams squash distances so that everything fits on one screen. Gravity Lab keeps the real sizes and distances. It also offers a "readable" scale that brings the planets closer together so they're easier to see. You can switch between the two at any time and see how much empty space there really is.

The other goal is to make physics something you can play with. It's one thing to read that the Moon may have formed when a Mars-sized world hit the young Earth. It's another to set up that collision yourself and watch a ring of debris form. Gravity Lab tries to make every result explainable. When something happens in the sandbox, a report says what happened and which physics caused it.

Real data, clearly labelled

Wherever real measurements exist, Gravity Lab uses them. Planet and moon positions come from published orbital elements. The exoplanets come from NASA's Exoplanet Archive. Spacecraft follow their real flight paths. Earth, Mars and the Moon are mapped from real imagery and elevation data. Where nobody has measured something, such as individual planets in another galaxy, Gravity Lab can show an example, but it is always labelled simulated. Read more in What's real and what's simulated.

Data and credits

The physics models are based on published research, which the guides cite where it matters. Examples include Collins, Melosh & Marcus (2005) for impacts, Toomre & Toomre (1972) for galaxy collisions, and Alcubierre (1994) for warp drives.

Free, and in your browser

Gravity Lab is free to use and needs no account or download. It runs on desktops, laptops, tablets and phones. A graphics quality setting (Ultra, Balanced or Battery saver) keeps it smooth on slower devices. It's currently in beta, so new features arrive often and some things may change.

Contact

Found a bug, spotted something that isn't quite right, or have an idea? Email [email protected]. Corrections to the science are especially welcome.