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Cometary habitats for primitive life.
M K Wallis1, N C Wickramasinghe, F Hoyle
1School of Mathematics, University of Wales, Cardiff.
Advances in Space Research : the Official Journal of the Committee on Space Research (COSPAR)
|January 1, 1992
Summary
Comet Halley studies suggest its insulating crust may harbor primitive life. Subsurface ice and potential lakes could support organisms if provided with energy sources, especially for radiation-resistant species capable of long hibernation.
Area of Science:
- Astrobiology
- Cometary Science
- Origin of Life Studies
Background:
- Comet Halley's nucleus is largely covered by an insulating crust of pyrolyzed organic material.
- The subcrustal region is warmed and permeated by gases, creating a potential habitat.
- Cracks and crevices in contaminated ice within craters may also support life.
Purpose of the Study:
- To investigate potential habitats for primitive replicating and photosynthesizing organisms on comets.
- To assess the conditions required for life to exist in cometary environments.
- To understand the implications of cometary habitats for panspermia theories.
Main Methods:
- Analysis of data from Comet Halley studies.
- Modeling of subsurface environments on comets and icy moons (e.g., Europa).
- Consideration of energy sources and environmental triggers for habitability.
Main Results:
- The insulating crust of Comet Halley suggests a potential habitat for primitive organisms.
- Subsurface environments, including potential ice lakes, require specific triggers (e.g., impacts) and energy sources to become habitable.
- Cometary transfer of life necessitates radiation resistance and long hibernation capabilities.
Conclusions:
- Comets may provide viable habitats for certain types of primitive life.
- The conditions for life on comets are constrained but potentially achievable.
- Life's ability to survive transfer between celestial bodies depends on specific adaptations.
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