Planets

There are three main categories of planets: Solid planets, water giants and gas giants. Even moons are considered as planets.

Scientific notes: Actually the term planet refers to celestial bodies orbiting a star with a gravity in a specific range. The gravity of a planet has to be strong enough to hold fluids in a stable state (hydrostatic equilibrium) which prevents them from escaping the planet and low enough to prevent nuclear processes to start as in stars. Some astronomical bodies, we call planets, are not considered as planets by this definition. Moons are natural satellites orbiting a planet and do not fall into the category of planets. However, some natural satellites are considered as planets because they fit their definition.

Terrestrial planet

Image	Class	Color	Exploration Value (with detailed surface scanner?)	Rarity	In game description
Icy Planet	Icy planete	White - Grey	~500cr	Very common	Ice world composed mainly of water ice. Worlds like this will not have much heating in the past, forming in the cooler regions of a star system and have retained many volatiles as solids withing their crust.
Rocky Planets	Rocky planete	White - Grey - Light blue - Light brown - Yellow	~500cr	Common	Rocky world with little or no surface metal content. Worlds like this have lost most of their volatiles due to past heating, and any metallic content will form a small central core.
Rocky ice planete	Rocky ice planete	White - Grey - Light blue - Light brown	~500cr	Uncommon	Rocky ice world. Typically formed in the cooler regions of star system these worlds have a small metal core and thick rocky mantle with a crust of very deep ice. Geological activity is common in these worlds because of the large quantities of volatiles in the crust, often creating a thin, sometimes seasonal atmosphere.
Variety of High Metal Content Planets	High metal content planete	Brown - Dark brown - Beige	2,500cr	Uncommon	Meta-rich world with a metallic core. Worlds like this can have metallic ores near the sruface in places, especially around areas of past volcanism.
	Metal rich planete	Brown - Black (sometime with visible lava)	~5,000cr	Rare
Water World	Water world	Blue with green, brown and white	unknown (guess ~10,000cr)	very rare
	Earth-like world	Blue with green, brown and white	~10,000cr	Extremely rare
Ammonia World	Ammonia world	Light brown	unknown (guess ~10,000cr)	Very rare

Water Giants

Water Giant

• Very rare.
• Color: Blue
• Exploration value: unknown

Gas Giants

Image	Class	Exploration Value (with detailed surface scanner?)	Rarity	Description
Class I Gas Giant	I	1,000 - 1,500cr	Rare	Class I or Jovian gas giants have primarily hydrogen and helium atmospheres. Coloration comes from clouds in the upper atmosphere of ammonia, water vapour, hydrogen sulphide, phosphine and sulphur. The temperature at the top of their upper cloud layers is typically less than 150 K.
	II	5,000cr	Very rare
Class III Gas Giant	III	1,000 - 1,500cr	Rare
	IV	1,000 - 1,500cr	Rare
Gas giant with ammonia based life	Gas giant with ammonia-based life	1,000 - 1,500cr	Very rare	Gas giant with ammonia-based life. This is primarily a hydrogen and helium-based atmospheric gas giant, but a little below the surface cloud layers,life exists based in the ammonia-cloud layer. The chemistry of this gaseous region is far from equilibrium, with a surprising excess of oxygen and many carbon-based compounds giving it some vivid colours. As with many such gaseous living systems, it is underpinned by vast quantities of free-floating radioplankton - tiny carbon-based algae, each retaining small quantity of liquid ammonia, extracting their energy from the intese radiation flux.