# Energy Absorption Rate

The Energy Absorption Rate represents the total rate at which energy is added to an object from sources in the simulation, such as stars or tidal friction. This property is used to calculate the change in the object's temperature over time.

The Energy Absorption Rate is a read-only property that is continually calculated by Universe Sandbox as the sum of the incoming energy rates, or powers, from all sources in the simulation, including Stellar Power, Atmosphere Power, Tidal Power, Supernova Power, and Gas Drag Power.

## Property Details

### Location

For Planetary Body objects, the Energy Absorption Rate property can be found in the Energy Flow section of the Surface tab. For Stars, Black Holes, and Human-Scale Objects, the Energy Absorption Rate property can be found in the Temperature tab.

### Units

Energy Absorption Rate can be viewed using the following units:

• Solar luminosity (L star) = 3.846×1026 W
• Watts (W) is the SI unit for luminosity.

## Simulation Effects

### Surface Temperature

At each simulation time step, the change in the temperature of each point on the object's surface, ΔT, is calculated using the Energy Absorption Rate, Pabs, the Energy Radiation Rate, Prad, the time step, Δt, and the object's Surface Heat Capacity, C, using