An ocean planet (also called a waterworld) is a type of planet whose surface is completely covered with an ocean of water.


They begin as a comet-like mixture of roughly half water and half rock by mass. Ocean planets are likely to migrate inward and outward as they form, presenting the possibility that icy planets could move to orbits where their ice melts into liquid form, turning these planets into ocean planets.

The oceans on these planets are hundreds of kilometres deep, much deeper than the oceans on Earth. The immense pressures in the lower regions of these oceans can lead to the formation of a mantle of exotic forms of ice. This ice is not necessarily as cold as conventional ice. If the planet is so close to its host star that the water's temperature reaches the boiling point, the water will become supercritical and lack a well-defined surface. Even on a cooler water dominated planet, the atmosphere can be much thicker than that of Earth, and composed largely of water vapour, producing an extremely strong greenhouse effect.

Small ocean planets have less dense atmospheres and lower gravity; thus, liquid evaporates much more easily than on a more massive ocean planet. Theoretically, these planets would or could have much higher waves than their more massive counterparts due to the lower gravity.

Resources Reserves

Below, you can consult the resource reserve ranges according to rarity:



4,5M - 5,5M

5,14M - 6,28M

159K - 194K


4,72M - 5,77M

5,4M - 6,6M

166K - 204K


5,17M - 6,32M

5,91M - 7,22M

182K - 223K


5,85M - 7,15M

6,68M - 8,17M

206K - 252K


6,75M - 8,25M

7,71M - 9,42M

238K - 291K

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