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The Ladder of Life Detection
Marc Neveu1,2, Lindsay E Hays2,3, Mary A Voytek2
11 NASA Postdoctoral Management Program Fellow, Universities Space Research Association , Columbia, Maryland.
Astrobiology
|June 5, 2018
Summary
The Ladder of Life Detection provides a framework for designing space missions to find microbial life. It uses past lessons and defines criteria for evidence of life, aiding future astrobiology research.
Area of Science:
- Astrobiology
- Planetary Science
- Microbiology
Background:
- Previous life detection missions have faced challenges in interpreting ambiguous results.
- Defining robust criteria for biosignatures is crucial for advancing astrobiology.
Purpose of the Study:
- To introduce the Ladder of Life Detection, a tool to guide the design of extraterrestrial life detection investigations.
- To establish criteria for convincing evidence of indigenous microbial life.
- To stimulate discussion on biosignatures and measurement techniques for robotic space missions.
Main Methods:
- Reviewing historical life detection attempts and their outcomes.
- Identifying and categorizing features of life and their measurability.
- Developing decision rules to differentiate between biological and abiotic origins of detected signals.
Main Results:
- The Ladder categorizes life-detection measurements based on their likelihood of indicating life.
- A set of decision rules is proposed to rigorously evaluate potential biosignatures.
- Past and future life detection missions are evaluated using the Ladder's framework.
Conclusions:
- The Ladder of Life Detection serves as a foundational tool for designing future life detection missions.
- It emphasizes the need for rigorous scientific debate on the definition and detection of extraterrestrial life.
- The tool is intended to evolve with ongoing research in astrobiology and instrumentation.
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