Solar Systems Screensaver
Solar Systems is a free, in-browser screensaver that procedurally builds a miniature star system — a glowing sun with planets, moons and orbit rings turning against a field of twinkling stars. Every system is generated from scratch, and a fresh one appears every half-minute, so you never see the same arrangement twice. It runs full-screen with no download, and ESC exits.
How the Solar Systems screensaver works
When a system is generated, the screensaver picks a sun color and lays out the planets at steadily increasing orbital radii, so the innermost world hugs the star and each successive planet sits a little further out, just like a real system. Each planet gets a random size and a color from a fixed palette, and is drawn with a subtle dark terminator shadow on one side to suggest a lit and unlit hemisphere.
Orbital speed follows a Kepler-style rule: a planet's angular speed scales with 1 divided by the square root of its orbit radius, so inner planets sweep around quickly while outer ones crawl. The Orbit speed control multiplies all of these together, letting you speed the whole clockwork up or slow it to a stately drift.
Roughly six in ten planets are given one to three moons when the Moons toggle is on, each circling its planet on its own little orbit at its own rate. Behind everything, about ninety background stars twinkle by gently oscillating their brightness, and when Show orbit rings is on, faint circles mark each planet's path.
Because it's a screensaver, nothing is permanent: each generated system runs for about 28 seconds and then the screensaver discards it and procedurally generates a brand-new star, palette and set of planets, so the screen is always evolving.
A worked example
With the defaults — 6 planets, Orbit speed 4, Show orbit rings on, Moons on — you get a sun ringed by six concentric orbit circles, inner planets racing around while the outer ones drift, several of them trailing a moon or two. After about 28 seconds the whole system dissolves and a new one is built. Crank Planets to 10 for a busy system, or set Orbit speed to 1 for a calm, almost-still tableau.
Settings & tips
- Turn on Show orbit rings to make the planetary paths visible as faint circles around the star.
- Lower Orbit speed to 1 for a slow, meditative drift, or raise it to 10 to watch the whole system spin.
- Toggle Moons off for a cleaner look, or on to give planets their own little orbiting companions.
Frequently asked questions
- Is the Solar System screensaver free?
- Yes. It runs free in your browser with no download or account. Open the page, let it fill the screen, and press ESC to exit.
- Does it show a new system over time?
- Yes. Each procedurally generated star system runs for about 28 seconds, then the screensaver builds a brand-new star, palette and set of planets.
- Why do inner planets move faster than outer ones?
- Orbital speed follows a Kepler-style rule where angular speed scales with one over the square root of the orbit radius. That makes planets close to the star sweep around faster than distant ones.
- Can I add moons and orbit rings?
- Yes. You can toggle moons, which gives many planets one to three orbiting companions, and toggle orbit rings, which draws a faint circle along each planet's path.
- How many planets can it show?
- You can set anywhere from two to ten planets. The screensaver lays them out at increasing distances from the central star.