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Carbon Worlds

Graphite-black planets with diamond mantles.

When carbon outweighs oxygen, a planet's whole mineralogy flips: instead of silicate rock it builds graphite plains, carbide ridges, and - under pressure - a mantle of diamond. Astronomers predict them around carbon-rich stars (55 Cancri e is the famous candidate). They form water-poor and lifeless, but few worlds glitter like a coal-black planet under a close sun. Build one by pushing carbon past oxygen on a rocky recipe.

Carbovore
Carbovore
Carbon WorldHabitability 39
Aug 9, 2026
Carbovore
Carbovore
Carbon WorldHabitability 39
Aug 11, 2026
Diamond Planet I
Diamond Planet I
Carbon WorldHabitability 30
by StargazerAug 4, 2026
diamond planet
diamond planet
Carbon WorldHabitability 12
Aug 7, 2026

See all carbon worlds on Explore →

Surface views from three worlds: rocky ground under a ringed sky, a cloud deck, and a lit desert

New: Stand on Your World 🏔️

Every planet you build can now be seen from the ground. The terrain, the color of the sky, the weather and what hangs overhead are all read from the same numbers that shape the globe — so a thin-aired world gives you sunlit rock under a near-black sky crowded with stars, a runaway greenhouse seals you under an unbroken sulfur lid, and a gas giant leaves you in the cloud tops with nothing solid beneath you at all. If one of your moons wandered inside the Roche limit, what is left of it arcs overhead as rings.

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Enter your email and we'll send a 6-digit code — no password needed.
We only keep your email and the username you choose. We never share or sell your email, and we don't send marketing — we use it only to email you a sign-in code. Learn more.

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We're still building out the best experience we can — and we'd love your input. Tell us about features you enjoy, ideas you'd like to see, or pain points where something feels off, and we'll know where to look next.

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