Planets in Master of Orion can have six different sizes, though one is reserved to gas giants. Along with biome, mineral richness, gravity, and resources, size is one of the parameters defining a planet.
General information
| Type | Image | Colonizable | Max Cells | Moon Chance | Terraforming Cost Factor | Pollution Capacity | Pollution Absorption Factor | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tiny
|
 |
Yes | 8 | 25% | 35% | 250 | 60% | |||||
| Small
|
|
Yes | 12 | 25% | 50% | 275 | 80% | |||||
| Medium
|
|
Yes | 16 | 33% | 100% | 300 | 100% | |||||
| Large
|
|
Yes | 20 | 33% | 130% | 325 | 120% | |||||
| Huge
|
|
Yes | 24 | 50% | 170% | 350 | 140% | |||||
| Gas Giant
|
 |
No | 0 | 0% | 100% | 0 | 0 |
- Colonizable
- Whether colony ship can land on this planet.
- Max Cells
- How much population this planet size can shelter. The actual value also depends on the biome: half is multiplied by the farmable cell factor, half by the productive cell factor, so the maximum size can only be reached on Gaia, tropical, grassland, and cavernous planets. (Note that aquatic species such as the Trilarians consider terran and ocean planets to be Gaia-class.) The maximum population can also be increased by advanced city planning and patched biospheres.
- Moon Chance
- Probability of a planet this size to be generated with at least one moon.
- Terraforming Cost Factor
- Modifier to the production cost of terraformation projects, including terraforming but also gaia transformation and all uber transformations.
- Pollution Capacity
- How much pollution must be accumulated before the planet's biome degrades.
- Pollution Absorption Factor
- A modifier to the planet biome's absorption factor. This requires the Unofficial Code Patch.
Population Growth
Population growth depends on planet size. A smaller planet will reach its population cap faster than a larger one, not just because said population cap is lower, but also because population growth will be faster, all else being equal.
| Type | Image | Minimum Required | Maximum Required Start | Maximem Required End | |||||
|---|---|---|---|---|---|---|---|---|---|
| Tiny
|
|
75 | 80 | 170 | |||||
| Small
|
|
75 | 100 | 200 | |||||
| Medium
|
|
75 | 125 | 250 | |||||
| Large
|
|
75 | 150 | 300 | |||||
| Huge
|
|
75 | 180 | 350 |
- Minimum Required
- How many life points are required at a minimum for the population to grow.
- Maximum Required Start
- How many life points are required at a maximum while the planet's current population is less than half its population cap.
- Maximum Required End
- How many life points are required at a maximum once the planet's population has reached over half its population cap.
Moons
Larger planets are more likely to have moons. Having at least a moon allows to build the moon laboratory and the orbital shipyard on the planet, however there are no gameplay advantages to having two moons instead of just one, or to having larger moons instead of smaller ones.
| Type | Image | Moon Orbits | Small Moon | Medium Moon | Large Moon | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Tiny
|
|
1 | 100% | 0% | 0% | |||||
| Small
|
|
1 | 100% | 0% | 0% | |||||
| Medium
|
|
1 | 70% | 30% | 0% | |||||
| Large
|
|
2 | 50% | 30% | 20% | |||||
| Huge
|
|
2 | 20% | 30% | 50% |