Master of Orion Gravity Guide: Gravity Penalties, Planet Distribution (v55.1.1)

A detailed explanation of gravity in the game and the effects of gravity related attributes.

Master of Orion Gravity Guide

Gravity Penalties

Gravity penalties are applied when your race homeworld gravity level does not match the gravity level of the current planet. It applies to all population outputs except taxes (food, research, and production). This penalty is calculated by multiplying your final population output by the gravity penalty (in decimal) and subtracting that from your output.

Gravity penalties are determined by the homeworld gravity and the gravity of the current planet.

###	High Gravity Planet	Normal Gravity Planet	Low Gravity Planet
High Gravity Homeworld	0% Penalty	25% Penalty	50% Penalty
Normal Gravity Homeworld	50% Penalty	0% Penalty	25% Penalty
Low Gravity Homeworld	50% Penalty	25% Penalty	0% Penalty

This can be a little deceptive since bonuses and penalties aren’t additive. Example: if you have a production bonus of 25% and a gravity penalty of 25%, your final output for 1 base output is:

(1+.25)(1-.25) = .9375

It’s not 1 like one would expect. This becomes even more pronounced with a 50% bonus and a 50% penalty, where 1 base output becomes:

(1+.5)(1-.5)=.75

This means having a 50% bonus and a 50% gravity penalty turns into a net 25% penalty instead of the two canceling each other out.

The same logic applies when combining a gravity penalty with a race penalty. Example: a 25% gravity penalty and a 25% race penalty would turn 1 base production into the following:

(1-.25)(1-.25) = .5625

This ends up being around a 44% penalty, slightly better than a 50% penalty.

Some More Mechanics
Leader bonuses provide a bonus multiplier to the adjusted population output (population output after gravity penalty is applied) + building outputs + research trait outputs, but do not seem to apply a bonus to planet specials such as artifacts. Just like with race attributes, a leadership bonus doesn’t cancel out gravity penalties additively.

Gravity penalties do not seem to affect research trait outputs, such as heightened intelligence (+1 research per researcher).

Gravity penalties only apply to population outputs, not to building outputs such as automated factories (+2 production). However, gravity penalties apply to population output increases from buildings, such as neutron colliders (+1 production per producer).

Note: The game currently has a bug that does not properly display the output from buildings if you have any workers assigned to production. It will still correctly calculate the total, however.

Planet Distribution

To get an idea of how many of each planet type a typical game would have, here’s the results for a normal cluster with 6 AI players (seed 1000, balanced condition).

High Gravity Planets	11
Normal Gravity Planets	49
Low Gravity Planets	17
Volcanic Planets	15
Asteroids	20
Gas Giants	18
Orion	1
Homeworlds	7

The immediate conclusion is that high gravity and low gravity homeworlds are absolutely not worth it. The wide majority of planets are of normal gravity based on this distribution and choosing any other gravity type would be crippling.

Note: The volcanic planets are counted separately since they aren’t very useful to custom races and Silicoids already have the tolerant trait. Orion is a special case since it is the best planet and always has normal gravity. Asteroids can be turned into normal gravity planets and gas giants can be turned into high gravity planets.

Is the Tolerant Trait Worth it?

That is the big question. Let’s take a look at the cost of gravity generators.

Research Cost

Physics	55
Advanced Magnetism	110
Neutron Physics	215
Artificial Gravity	425
Total	805

The research is not particularly significant and could be easily done within 100 turns or less.

The cost of the generator itself is 160 production or 1280 credits. Even with a booming economy, those credits are quite steep and better spent elsewhere. This leaves the production.

Assuming the distribution example is representative of a typical map and ignoring planet construction, the gravity penalties for a normal gravity race would be an average:

(11*50%+49*0%+17*25%)/(11+49+17) = 13% penalty, give or take.

The Argument Against Tolerant
Since tolerant requires 6 points, it seems like +50% bonus to production is a better option than negating a 13% penalty to all outputs, especially since it’s temporary until gravity generators come online.

The Argument For Tolerant
Let’s take a look at it differently. High gravity planets make up around 15% of the useful planets, have the largest population sizes, and that doesn’t include the low gravity planets. If you count gas giants, the number becomes closer to 25%. Assuming a generous 4 production after penalties, it would take 40 turns to get a gravity generator built, during which time food production (and in turn, population growth) would be crippled and all population would be dedicated to nothing but building that gravity generator. For people who don’t want up to 25% of their planets to be stunted during the early part of the game where fast growth is important, this could be considered a huge boost.

This can also be a make or break for an early game planet since a gravity penalty planet with +1 food per cell would be incapable of supporting a population and a +2 would have to choose between feeding itself and production, even with additional population units transported in.

Planets and Their Gravity Levels

For every planet, the gravity type is determined by its size and minerals.

###	Huge	Large	Medium	Small	Tiny
Ultra Rich	High	High	High	Normal	Normal
Rich	High	High	Normal	Normal	Normal
Abundant	High	Normal	Normal	Normal	Low
Poor	Normal	Normal	Normal	Low	Low
Ultra Poor	Normal	Normal	Low	Low	Low

There are special exceptions such as Orion which is normal gravity and a home planet which is dependent on the race.

Note: Asteroids transform into large abundant planets with normal gravity and gas giants transform into huge abundant planets with high gravity.