Frequently asked questions

Yes. Everything in Gravity Lab is free to use, with no account and no download.

A modern web browser (Chrome, Edge, Firefox or Safari) with graphics acceleration switched on. It works on desktops, laptops, tablets and phones. On touch screens, an on-screen joystick replaces the keyboard.

Drag to look, W A S D to fly, and click any world to fly to it. Press / to search for anything by name. Press Esc at any time for the full list of controls. See Getting started.

Yes. A quiet soundscape changes with where you are, from wind in an atmosphere to the roar near the Sun, and includes real NASA recordings such as Cassini's radio recordings of Saturn. Sound effects scale with the physics, and there's an optional narrator. You can adjust all of it, or turn it off, in ⚙ Settings.

Open ⚙ Settings and choose a lower graphics quality: Balanced or Battery saver. Closing other heavy browser tabs helps too. If everything is extremely slow, check that your browser's hardware or graphics acceleration is switched on. Without it the browser draws 3D graphics on the processor instead of the graphics card, which is far slower. Gravity Lab detects this and switches to its lightest mode, but the real fix is the browser setting.

That usually means the graphics card reset, which can happen when a device overheats or runs low on memory. Gravity Lab shows a message offering to reload in Battery saver, and starts in that gentler mode on your next visit too. If it keeps happening, choose Battery saver in Settings.

Wherever real data exists, Gravity Lab uses it. Planets, moons and spacecraft are at their real positions for the date on the clock, satellites use live orbit data, and the exoplanets come from NASA's Exoplanet Archive. Things nobody has observed, such as planets in other galaxies, are clearly labelled as simulated. See What's real and what's simulated.

You're in Readable scale, which enlarges the planets and squeezes the distances so you can see everything at once. Switch the Scale control to True size for real sizes and distances. Be ready for a lot of empty space.

Yes. The gas giants have no solid surface, so you can keep descending through the cloud layers toward the core. Venus has a real descent: through its sulfuric-acid clouds to the ground, mapped from the Magellan spacecraft's radar, with the temperature and pressure rising as you go.

Search for "ISS" and Gravity Lab takes you there. Its position comes from live orbit data, so it's where it really is, circling the Earth about every 90 minutes.

It uses real Newtonian gravity on the real Solar System, starting from the current positions and velocities of the planets. Collisions, explosions and impacts follow published research models. Some outcomes are simplified, and impact casualty figures are estimates. See Sandbox Mode.

Not yet. Saving your own universes and tracking mission progress are coming with optional accounts. Your settings and your Theory Lab equations are already kept on your own device. Theory Lab pages can also be shared as links.

Missions are coming soon: planetary defence (deflecting a real collision-course asteroid) and sandbox challenges like lighting a new star or giving Earth a second moon.

No personal data. There are no accounts and no tracking cookies. Visits are counted with Cloudflare Web Analytics, which stores nothing on your device. The Privacy Policy has the details.

Yes, and we'd love to hear how it goes. It runs in a browser with nothing to install, which suits school computers. The guides explain the science behind what students will see.

Email [email protected] with what you were doing and, if you can, your device and browser. Corrections to the science are especially welcome.