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Updated: Jul 8, 2026
06:57
Determining Basal Energy Expenditure and the Capacity of Thermogenic Adipocytes to Expend Energy in Obese Mice
Published on: November 11, 2021
An energy balance concept for habitability
1NASA Ames Research Center, Moffett Field, California 94035, USA. tori.m.hoehler@nasa.gov
Astrobiology
|January 1, 2008
Summary
Life requires a balance between energy demand and environmental energy supply. This energy balance framework quantifies habitability, guiding the search for extraterrestrial life and understanding life
Area of Science:
- Astrobiology
- Biochemistry
- Planetary Science
Background:
- Habitability is defined by the balance between biological energy demand and environmental energy supply.
- Life requires specific energy 'voltage' and 'power' thresholds, influenced by biochemistry and environmental conditions.
Purpose of the Study:
- To formulate habitability as an energy balance problem.
- To establish quantitative constraints for habitability applicable to diverse environments, including those beyond Earth.
Main Methods:
- Analyzing biological energy demands (minimum requirements for 'voltage' and 'power').
- Identifying environmental constraints on energy transduction rates (e.g., energy source availability, transport limitations, biochemical processing limits).
- Defining habitability as the point where realized energy transduction meets or exceeds biological demand.
Main Results:
- Habitability is achieved when energy transduction rate equals or exceeds biological energy demand.
- Deviations from optimal conditions and resource limitations increase biological energy requirements.
- Environmental factors and biochemical capacities limit the potential rate of energy transduction.
Conclusions:
- The energy balance construct provides a universal framework for assessing habitability.
- This framework can prioritize targets for extraterrestrial life detection missions, including those with non-water solvents.
- It offers quantitative constraints for habitability assessments in diverse planetary systems.
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