TerrainPalette

aeolianreadonly

Whether wind can sort fines here at all, 0..1.

airThicknessreadonly

basaltreadonly

Flood basalt: the dark smooth plains that pond in basins.

evaporitereadonly

Evaporite: the bright crust a standing liquid leaves when it goes.

evaporiticreadonly

Whether a liquid ever stood here to leave a crust behind, 0..1.

freshGainreadonly

How much brighter impact-fresh material is than the ground it lies on.

Lunar ray systems run 1.3 to 1.8 times the local albedo, which is what makes Tycho visible from Earth with no instrument at all.

hazeColorreadonly

The haze's own color, unnormalized — what the air in front of the ground looks like.

A different job from skyColor and therefore a different field. That one is a tint on the light arriving at the surface and carries no brightness; this one is the aerial veil, and its value is the veil's own.

icereadonly

Condensed volatiles: caps, frost and an ice shell.

liquidreadonly

The liquid the sea sheet and the rivers are drawn in, or null where nothing runs. oceanColor is its deep color where it exists; the absorption and the glow are the sheet's alone.

lunarLambertreadonly

How much of the photometric blend is Lommel-Seeliger.

The same split tuningFor gives the body material, and it has to be the same or the streamed ground and the sphere behind it shade differently at the terminator: a powder backscatters, so an airless world is nearly flat across its disk and falls off a cliff at the shadow line, while a surface under air is much closer to Lambert.

maxElevationreadonly

Peak-to-datum relief, meters — what altitude is measured against.

mineralHighreadonly

mineralLowreadonly

Multiplicative tint at the two ends of the body's compositional ramp.

oceanColorreadonly

What deep water looks like from above.

pigmentreadonly

What grows: the biosphere's pigment as a deposit, laid where the cover's biota channel says. Absolute rather than a ratio of the base, because chlorophyll is the same green on any rock.

regolithreadonly

The mature mantle — dust and rubble — which is most of an airless world.

reposereadonly

The steepest ground loose material rests on, as 1 − cos θ.

The angle of repose for dry granular material is about 33° whatever it is made of, which is a fact about friction rather than about a planet. Past it a slope sheds its mantle and shows the rock underneath, and that is the single thing that makes a crater wall read as a crater wall.

rockreadonly

Exposed bedrock: what a slope too steep to hold anything wears.

sandreadonly

Wind-sorted fines: dune seas and drift.

seabedreadonly

The seabed: silt and sand under the water, and what shows through it.

Paler than the regolith, because a shelf is sorted fines rather than weathered rock, and it is what a shallow sea is turquoise over.

seaLevelreadonly

The ocean datum in meters, or null on a dry world.

sheetreadonly

Whether the sea is drawn as a sheet over the seabed, 0..1.

One on a mapless body with a sea; zero on a mapped one, whose sea is in the photograph — the same carve-out the invented cover follows, because the generated datum and the map disagree about where the land is.

skyColorreadonly

What the sky over this ground is, as a tint of unit luminance.

The atmosphere shell in front of the terrain carries the light scattered between the camera and the ground; what it cannot do is put light on the ground, so this is the other half — and without it a Martian crater floor at low sun is black, which no photograph of Mars has ever been.

Normalized, because how much light the sky delivers is airThickness and this is only what color it arrives in. Left as the haze's own values the two multiply and a thin warm sky is dimmer than a thin blue one for no reason anybody could name.

sunsetTintreadonly

What a low sun turns, and how much air there is to turn it.

terminatorreadonly

Half-width of the terminator, in cosine of the incidence angle.

textureKeyreadonly

The archive's texture-set key for this body, or null.

A key, not a path, for the reason BodyAppearance.texture is one — and it is here because it is what tells the material which of two things the colors beside it are: reflectances, or ratios to multiply a published map by.