Life Likelihood

The Life Likelihood property of an object is a measure of how similar the object's habitability-related properties are to the Earth's. The Life Likelihood property is read-only and is calculated automatically by Universe Sandbox.

Universe Sandbox calculates an object's Life Likelihood based on its Earth Similarity Index, tangential speed at equator, liquid level, and atmosphere mass. The Life Likelihood is given by

$LL=(ESI*LL_{spin}*LL_{water}*LL_{atmo})^{1/4},$

where ESI is the Earth Similarity, and LL_spin, LL_water, and LL_atmo are the individual contributions to the Life Likelihood of the tangential speed at equator, liquid level, and atmosphere mass, respectively. For example, if the object's tangential speed at equator is v_obj and the Earth's is v_earth, then the contribution of tangential speed at equator to Life Likelihood is

$LL_{spin}=\left(1-{\frac {v_{obj}-v_{earth}}{v_{obj}+v_{earth}}}\right)^{w_{spin}}.$

The contribution of each property is weighted according to the following values:

• w_ESI = 2.57
• w_spin = 0.87
• w_water = 1.70
• w_atmo = 4.32

Properties with larger weights have larger effects on the object's Life Likelihood.

Lights and Vegetation requirements:

As of Terraforming Update 34, City Lights and Vegetation now require a habitable gas pressure of 0.6 to 1.6 bars and a new habitable temperature of -25 °C to 55 °C (previously -55 °C to 55 °C) and to appear when set to “If Habitable.”

Property Details

Location

The Life Likelihood property of an object is located in the Comparisons section of the Composition tab of the object's properties panel.