Eight Worlds
Four small rocky planets, two gas giants and two ice giants — all orbiting one ordinary star. Click any planet to open its numbers. Every world below is drawn in pure CSS: no images are loaded.
Sizes are adjusted so every planet stays visible — not to scale. Press the button above to see the real proportions.
Why the planets split into groups
Rocky planets
Mercury, Venus, Earth and Mars formed close to the young Sun, where it was too hot for ice to survive. Only heavy rock and metal could condense, so these worlds ended up small, dense and solid.
Gas giants
Beyond the "frost line", ice survived and planets grew huge fast. Jupiter and Saturn got big enough to hold onto hydrogen and helium — the lightest and most common elements in the universe. They have no solid surface to stand on.
Ice giants
Uranus and Neptune formed further out and later, so they captured much less hydrogen. They are mostly water, ammonia and methane — and it is the methane that makes them look blue.
Moon counts are confirmed moons and change as astronomers find more — Saturn gained 128 in 2025. Figures follow NASA's planetary fact sheets.