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Saturn, the real one
Saturn is the sixth planet from the Sun and the second largest. It is a giant ball of hydrogen and helium with no solid surface, so light for its size that it would float in a bathtub big enough to hold it. Its rings are made of countless pieces of ice and rock, from grains of dust to boulders the size of a house.
274Confirmed moons, the most of any planet (128 were announced in 2025)
10 h 33 minOne day: Saturn spins faster than any planet except Jupiter
29.4 yearsOne year: the time it takes to go once around the Sun
60,268 kmRadius at the equator: the unit we measure everything in on this site
0.69 g/cm³Average density, lower than water
26.7°Axial tilt, which is why we see the rings from above and below over the years
~10 mTypical thickness of the main rings, though they span about 270,000 km
13 yearsHow long the Cassini spacecraft orbited Saturn, from 2004 to 2017
Six moons, two rings, one planet
Of Saturn's 274 moons, we picked the small ones that live right at the edge of the rings, plus Enceladus a little further out. Each one lends its name and its character to a page.
| Moon | Size | Orbit | One lap | What makes it special | Page |
|---|---|---|---|---|---|
| Atlas | 30 km | 137,670 km | 14.4 h | A ridge of ring dust round its middle makes it look like a flying saucer. | ServicesThe Titan who carries the sky. Services carry the work. |
| Prometheus | 86 km | 139,380 km | 14.7 h | Shepherds the inner edge of the thin F ring and pulls streamers out of it. | ResearchHe brought fire, and knowledge, to people. |
| Pandora | 81 km | 141,720 km | 15.1 h | Shepherds the outer edge of the F ring, working as a pair with Prometheus. | ClientsHer jar was full of surprises. Clients is full of projects. |
| Janus | 179 km | 151,460 km | 16.7 h | Shares its orbit with Epimetheus. Every four years the two swap places. | AboutThe god of doors and beginnings: the first door into the studio. |
| Epimetheus | 116 km | 151,410 km | 16.7 h | Janus's partner. They never collide: they trade orbits as they meet. | LearnHis name means "afterthought": looking back at how things are made. |
| Enceladus | 504 km | 237,950 km | 32.9 h | Geysers at its south pole spray ice into space and feed Saturn's E ring. | ContactThe moon that reaches out. |
The rings follow the same idea. The inner ring matches Saturn's bright B ring and leads to The Wallflowers. The outer ring matches the A ring and leads to Le Cercle. The dark gap between them is the Cassini Division. The planet itself opens the client portal, Saturnio Cloud.
The planet is the menu
PointHover a ring, a moon or the planet. It lights up, everything else fades back, and a label tells you where it leads.
ClickClick to travel there. The screen breaks into characters for half a second while the next page arrives.
Read the tagEvery page carries its moon's name in the blue tag at the top. That tag is also the hidden door to this page.
Come backThe Back button returns you to the planet. The menu in the corner lists every page for anyone who prefers words to moons.
How the system was made to fit a screen
A true-to-scale Saturn would not fit on a phone, and its little moons would be invisible. So we kept the real relationships (order, timing, tilt) and adjusted only what a screen cannot show.
One unit
R = min(17% of width, 32% of height)
Everything is measured in Saturn radii, R. The planet is sized from the screen, so the whole system scales from a phone to a cinema display.
Real timing
lap = 30 s × real period ÷ 14.4 h
Atlas laps the planet in 30 seconds. Every other moon keeps its true ratio to Atlas, so Enceladus takes 68.5 seconds, just as it really takes about 2.3 times longer.
Kepler's third law
speed ∝ r−1.5
Each row of ring dots turns at its own speed, inner rows faster than outer ones, the way real ring particles orbit.
Room to click
2.28–2.51 R → 2.31–2.72 R
The real moons crowd into a thin band. We spread them out so each one can be clicked, and pulled Enceladus in from 3.95 R to 2.88 R so it stays on screen.
The view
pitch 0.40 rad · roll −0.32 rad
We look down on the rings at about 23°, close to the widest view Saturn shows us from Earth (about 27°, roughly every 15 years), and tilt the whole planet slightly.
Tidal lock
angle = atan2(y, x)
Like the real moons, each one always turns the same side to Saturn. Their long axes point at the planet as they orbit.
The dots
brightness = light · surface normal
The planet, moons and Contact globe are rows of dots on a sphere, turned with a simple projection and lit from the upper left. Brighter dots face the light.
Sizes you can see
30 km → 504 km = 2.4 px → 6.4 px
Enceladus is 17 times wider than Atlas. We kept the order of sizes but narrowed the range, so even the smallest moon stays a target.