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Pax Abyssi
Science // Barren and ice worlds

Barren and ice worlds, grown from their type

Pax Abyssi's airless and icy moons and planets are procedural. Our planet generator grows each one from its type in the simulation and a seed taken from the body itself, so no two moons of a type are the same place, and you can fly down to any of them and walk to the horizon.

In Pax Abyssi: eight of the 66 barren and ice types, each a render from our planet generator.

01 // In flight

Moons and ice worlds as you see them from the seat

Frames from the game, the HUD off. Every moon is on its true orbit round its parent, lit by the system's own star, so a giant hangs behind its moons where the orbits put it. Select a frame to see it full size.

Two crescents against black: a ringed giant's thin lit edge with faint rings arcing round it, and before its night side the smaller crescent of an icy moon, the star bright at upper left, open full size
Cervantes VI and its Europa-type moon as two crescents, the star behind them both. The moon is on its true orbit, 300,000 km out, and the ship sits just beyond it.
In-game capture, pre-alpha, HUD off
A large grey-tan moon with dark old terrain overlapping the top of a pale blue-green ice giant, broad ringlets sweeping across the giant and out of the frame, open full size
Cervantes VII-I, a Ganymede-type moon of dark old terrain and bright grooved ice, in front of its ringed ice giant.
In-game capture, pre-alpha, HUD off
A white icy moon crossed by red-brown lines high on the right, the cream-banded limb of a ringed gas giant filling the bottom of the frame, open full size
Cervantes VI-I, a Europa-type moon, its young ice crossed by red-brown lines, above the banded cloud tops of its giant.
In-game capture, pre-alpha, HUD off
02 // Procedural

No painted maps, no hand-built worlds

In the game11,359 worlds to land on

A barren or icy body in Pax Abyssi takes its world from its type. The generator reads what the simulation says the body is, a basalt planet, a Europa-type moon, an iron world, and builds that world at the body's true radius and gravity, turned and seeded by the body's own identity. Nothing is built by hand for one place. In the catalogue systems alone that makes 11,359 planets and moons you can land on today: 5,005 planets and 6,354 moons, 8,001 of them barren or icy.

The ground is grown as you descend. Gravity pulls toward the centre of a real sphere, craters follow the size laws measured on the Moon and Mercury, and on a 3,000 kilometre world the surface resolves to triangles of about 0.7 metres under your boots.

Every planet class is moving to procedural generation. The gas giants went first, and every one is now grown by our giant generator. Barren and ice worlds are moving onto it now, and lava worlds, greenhouse worlds and arid worlds are already there, every type. The rest of the planet classes follow until the generator replaces every baked texture in the galaxy.

What stays is the research. Each of our 107 planet types rests on its own study of the real science: the papers, the bodies it is modelled on, the albedos and colours measured by spacecraft. That research is the generator's brief. A type's look takes its layout and hue from our studies of that type and its brightness from the measured albedo of its real counterparts, and where the two disagree, the science wins.

In the gamegiants, barren, ice, lava and greenhousePlannedevery other planet class
03 // The data

What one planet is made of

The generator writes a whole planet as numbers before it draws a pixel. A gas giant is 21,408 of them, grown from about 300 in its look row and a seed of its own. A barren moon is 1,371; an icy moon crossed by a hundred lineae is 3,385. The game grows the ground from them as you fly.

A cream and brown banded gas giant with festoons curling into its white equatorial zone
Gas giant
Turbulent cold giant
GGC-AB-TU-1
21,408

numbers per planet, from a look row of about 300 and the planet's own seed

A sample of the data
Sim
A sample of the data
Bands12, equatorial zone 25°
Jet strength1.2
Belt turbulence0.45
Chromophore#8C4626, amount 0.45
Limb darkening, Minnaert k0.92
Convection cells16
Storms and features drawn18
Band table1,024 rows
Global settings28
A grey cratered moon with dark lava seas in its old basins
Barren moon
Barren rocky moon
M0-B1
1,371

numbers in the world, before the ground is grown from them

A sample of the data
Sim
A sample of the data
Built onHYG 96000 II-II, a real moon of the generated galaxy
Radius1,907.2 km
Surface gravity1.77 m/s²
Geometric albedo0.08
Craters30 m to 100 km, complex above 14.6 km
Basins45, from 330 to 2,669 km
Flooded with lava6 basins and 15% of the lowlands
Mare share17.9% of the sphere
A white ice moon crossed in every direction by long red-brown lines
Icy moon
Tectonic moon, the Europa type
T2-SB
3,385

numbers in the world, 2,914 of them its lineae

A sample of the data
Sim
A sample of the data
Built onHYG 11521 IV-I, a real moon of the generated galaxy
Radius1,354.9 km
Surface gravity0.76 m/s²
Mean temperature−164.7 °C
Geometric albedo0.62
Lineae100: 57 ridges, 13 troughs, 17 arcs, 13 scarps
Ridge width9 to 13 km
Cratersalmost none: the ice is young
04 // Barren worlds

40 barren types, from the Moon's grey to bare metal

In the game11 types landable, the rest in development

Airless rock, sorted the way a geologist would: by what the crust is made of, then by what shaped it, from impact and lava to the scarps of a shrinking planet. Every type the galaxy holds has its look designed for the generator.

In Pax Abyssi: every sphere is a render from our planet generator, lit from the same angle near full phase. Types in the game are the game's own render of the world you land on; the rest are drawn from their designed looks. Hover or focus a tile for its name.

  • In the game
  • In development
  • Planned

Barren moons

3 types · 1 in the game

Airless rocky moons, the commonest bodies in the galaxy you can land on. The Luna type is in the game: every one of its moons lands on its own true radius.

  • Barren rocky moon, barren world M0-B1: The Luna type: cratered grey highland, dark basalt in the old basins. In the game.M0-B1
  • Iron-rich moon, barren world M0-B2: Mercury-like: darker, warmer ground, iron in the crust. In development.M0-B2
  • Thin-atmosphere rocky moon, barren world M4-T: Basalt ground under a trace of air, carbon dioxide frost at the poles. In development.M4-T

Mercury-type planets

10 types · 10 in the game

Neutral grey rock with no air, Mercury's family. Every one of these planets is landable today; each subtype's own look follows the saturated highland onto the generator.

  • Saturated highland, barren world TBR-HC-SH: Craters on craters, cratered to saturation. In the game.TBR-HC-SH
  • Basin scarred, barren world TBR-HC-BS: Old multi-ring basins cut through the cratered crust. In the game, its own look in development.TBR-HC-BS
  • Ray scarred, barren world TBR-HC-RY: Bright rays flung from young craters across grey ground. In the game, its own look in development.TBR-HC-RY
  • Scarp network, barren world TBR-SC-SN: Lobate thrust scarps where the planet shrank as it cooled. In the game, its own look in development.TBR-SC-SN
  • Tectonised basin, barren world TBR-SC-TB: Basins broken by scarps and wrinkle ridges. In the game, its own look in development.TBR-SC-TB
  • Volcanic basin fill, barren world TBR-VP-BF: Lava plains pooled in the floors of the great basins. In the game, its own look in development.TBR-VP-BF
  • Extensive plains, barren world TBR-VP-EP: Smooth volcanic plains over much of the planet. In the game, its own look in development.TBR-VP-EP
  • Ghost crater plains, barren world TBR-VP-GC: Lava so deep that buried craters show only as rings. In the game, its own look in development.TBR-VP-GC
  • Graphite patches, barren world TBR-DK-GP: Dark carbon-rich crust, Mercury's low-reflectance material. In the game, its own look in development.TBR-DK-GP
  • Dark mantle, barren world TBR-DK-DM: A dark ilmenite-rich blanket over the grey crust. In the game, its own look in development.TBR-DK-DM

Charcoal basalt with no warm tones, its darkness set by titanium: the lunar seas grown to the size of a planet, sorted by how the lava came and what struck it after.

  • Flood basin, barren world TBB-FF-FB: One great basin flooded with dark lava. In development.TBB-FF-FB
  • Ghost maria, barren world TBB-FF-GM: Old lava seas worn back toward the highland. In development.TBB-FF-GM
  • Mixed maria, barren world TBB-FF-MM: Lava seas of several ages among the highland. In development.TBB-FF-MM
  • Spotted maria, barren world TBB-FF-SM: Many small dark lava ponds across the highland. In development.TBB-FF-SM
  • Blue charcoal, barren world TBB-HT-BC: High-titanium basalt, the blue-black of the youngest lunar seas. In development.TBB-HT-BC
  • High-titanium dark, barren world TBB-HT-HD: Near-black titanium basalt over most of the world. In development.TBB-HT-HD
  • Multiple rays, barren world TBB-IM-MR: Several bright ray systems across dark basalt. In development.TBB-IM-MR
  • Single ray, barren world TBB-IM-SR: One young crater's rays across the plains. In development.TBB-IM-SR
  • Terraced basin, barren world TBB-IM-TB: A terraced multi-ring basin, Orientale's kind. In development.TBB-IM-TB
  • Graben plains, barren world TBB-TC-GP: Basalt plains cut by sets of parallel graben. In development.TBB-TC-GP
  • Sinuous rille, barren world TBB-TC-SR: Lava channels winding across the plains. In development.TBB-TC-SR

Crusts rich in iron: rust where its oxides weather, bright metal where an iron-nickel body lies bare, the remains of a planet's core.

  • Hematite, barren world TBI-HM-SD: Rust-red iron oxide crust. In development.TBI-HM-SD
  • Magnetite, barren world TBI-MG-SD: Rust-brown magnetite with banded basins. In development.TBI-MG-SD
  • Metallic plains, barren world TBM-MT-SD: Silver to gunmetal iron-nickel plains. In development.TBM-MT-SD
  • Scarped metallic, barren world TBM-SC-SD: Impact melt plains on a metal world, cut by scarps. In development.TBM-SC-SD

Pale tan, never grey: fine bright regolith over the rock, sorted by age from fresh crust to old highland worn into palimpsests.

  • Palimpsest highland, barren world TBS-AH-PH: Old craters relaxed flat into pale rings. In development.TBS-AH-PH
  • Ray cratered, barren world TBS-AH-RC: Tan highland crossed by bright rays. In development.TBS-AH-RC
  • Rayed scarps, barren world TBS-AH-RS: Scarps and ray systems on the highland. In development.TBS-AH-RS
  • Saturation basin, barren world TBS-AH-SB: Highland battered to saturation around great basins. In development.TBS-AH-SB
  • Fresh ejecta, barren world TBS-BS-FE: Bright ejecta blankets around young craters. In development.TBS-BS-FE
  • Young crust, barren world TBS-BS-YC: A bright young crust with few craters. In development.TBS-BS-YC
  • Flat basin, barren world TBS-DP-FL: A basin filled flat and smooth with dust. In development.TBS-DP-FL
  • Pond mantled, barren world TBS-DP-PM: Dust ponds settled in the low ground. In development.TBS-DP-PM
  • Graben ridged, barren world TBS-MX-GR: Plains cut by graben and ridges. In development.TBS-MX-GR
  • Mature cratered, barren world TBS-MX-MC: Plains cratered for aeons, soft and worn. In development.TBS-MX-MC
  • Transitional, barren world TBS-MX-TR: Old highland grading into younger plains. In development.TBS-MX-TR
  • Young highland, barren world TBS-MX-YH: A freshly cratered highland with sharp rims. In development.TBS-MX-YH
In the wikiBarren rock worldNatural satellitePlanet classification
05 // Ice worlds

26 ice types, from Europa's lines to Pluto's basins

In the game15 types in the game

Moons and planets of frozen water, nitrogen and methane. Each look starts from a real body, Tethys, Titania, Enceladus, Europa, Ganymede, Pluto, and follows its science: bright young ice where an ocean resurfaces it, dark stained ice where it has lain for aeons.

In Pax Abyssi: every sphere is the game's own render of the world you land on, lit from the same angle near full phase. Hover or focus a tile for its name.

  • In the game
  • In development
  • Planned

Icy moons

7 types · 7 in the game

Every round icy moon type in the galaxy is in the game, each modelled on the real moon it is named for, from Tethys's great rift to Europa's red-brown lines.

  • Wispy ice, ice world T0-B6-WI: Dione and Rhea: cratered ice streaked with bright fault wisps. In the game.T0-B6-WI
  • Pure rift, ice world T0-B6-PR: Tethys: bright ice split by one great chasm. In the game.T0-B6-PR
  • Rift valley, ice world T0-B6-RV: Titania: grey-brown ice cut by deep canyons. In the game.T0-B6-RV
  • Dark material, ice world T0-B6-DM: Oberon: grey ice with dark-floored craters. In the game.T0-B6-DM
  • Plume moon, ice world T2-SA: Enceladus: blue tiger stripes and fresh fallout. In the game.T2-SA
  • Tectonic moon, ice world T2-SB: Europa: young ice crossed by red-brown lineae. In the game.T2-SB
  • Grooved moon, ice world T2-SC: Ganymede: dark old terrain against bright grooved ice. In the game.T2-SC

Ice worlds

3 types · 3 in the game

Planets of frozen water, nitrogen and methane, Pluto and Triton grown to planet size. All three are in the game.

  • Pristine, ice world TIW-PR-SD: Pale blue-grey ice, light craters, faint fine lineae. In the game.TIW-PR-SD
  • Cracked, ice world TIW-CR-SD: Turquoise ice under a net of dark fractures. In the game.TIW-CR-SD
  • Tholin-stained, ice world TIW-TN-SD: Orange-red tholin ground with clean-ice provinces. In the game.TIW-TN-SD

Subsurface ocean planets

5 types · 2 in the game

An ocean of liquid water under a shell of ice, warmed from below. The shell's face tells you what the ocean is doing.

  • Plume world, ice world TSO-PL: White ice, long blue fractures toward one pole, buff fallout. In the game.TSO-PL
  • Hidden vent, ice world TSO-HV: Quiet grey-blue ice, soft mottling and faint ridges. In the game.TSO-HV
  • In developmentTSO-TC
  • In developmentTSO-DY
  • In developmentTSO-BR

Ice super-Earths

11 types · 3 in the game

Icy planets up to twice Earth's width, heavy enough to hold a fifth of a bar to three quarters of a bar of air over the ice.

  • Cryovolcanic resurfacer, ice world SEI-CR-CH: White ice, blue fractures running round the globe. In the game.SEI-CR-CH
  • Ancient dark shell, ice world SEI-DS-AM: Dark brown shell, big bright ray systems. In the game.SEI-DS-AM
  • Tholin-stained, ice world SEI-TS-WS: Red-brown tholins around white nitrogen-ice basins, Pluto's look. In the game.SEI-TS-WS
  • In developmentSEI-CR-CM
  • In developmentSEI-DS-AD
  • In developmentSEI-TS-DP
  • In developmentSEI-HI-IX
  • In developmentSEI-HI-IV
  • PlannedSEI-NG-NC
  • PlannedSEI-NG-NF
  • PlannedSEI-HS-HM
In the wikiIce worldSubsurface ocean worldSuper-EarthNatural satellite
More science

The rest of the science