A Proposed Geobiology-Driven Nomenclature for Astrobiological In Situ Observations and Sample Analyses

Area of Science:

• Astrobiology and Astrobiological Context
• Geobiology and Geochemical Processes
• Planetary Science and Exploration

Background:

• Increased exploration for extraterrestrial life necessitates a common nomenclature for non-Earth biology and related processes.
• Earth as the sole data point for life introduces bias in defining and detecting life 'as we don't know it'.
• Challenges exist in mission planning and instrument selection due to the inherent bias in life detection strategies.

Purpose of the Study:

• To develop an improved nomenclature for classifying terrestrial features based on mineral-microbial interactions.
• To define categories: biotic (life-exclusive), biogenic (life-modified), abiotic (life-unaffected), and abiogenic (independent of life).
• To aid in deciphering returned samples and in situ analyses from Mars and ocean worlds.

Main Methods:

• Review and refinement of existing nomenclature for geological and biological features.
• Establishment of clear definitions for biotic, biogenic, abiotic, and abiogenic classifications.
• Discussion of hypothetical detection and preservation environments for extant and extinct extraterrestrial life.

Main Results:

• Proposed four-category classification system (biotic, biogenic, abiotic, abiogenic) for unambiguous identification of life-related features.
• Framework supports distinguishing life-generated structures and chemical patterns from non-biological ones.
• Identified critical considerations for future life detection missions and sample analysis.

Conclusions:

• The proposed nomenclature is crucial for interpreting data from Mars and ocean worlds, minimizing bias in life detection.
• Universal biosignatures supporting Darwinian evolution in extraterrestrial geological contexts are key considerations.
• The framework enhances geobiological interpretations within the broader astrobiological context.