Habitability Models for Planetary Sciences

Abstract

Habitability has been generally defined as the capability of an environment to support life. Ecologists have been using Habitat Suitability Models (HSMs) for more than four decades to study the habitability of Earth from local to global scales. Astrobiologists have been proposing different habitability models for some time, with little integration and consistency between them and different in function to those used by ecologists. In this white paper, we suggest a mass-energy habitability model as an example of how to adapt and expand the models used by ecologists to the astrobiology field. We propose to implement these models into a NASA Habitability Standard (NHS) to standardize the habitability objectives of planetary missions. These standards will help to compare and characterize potentially habitable environments, prioritize target selections, and study correlations between habitability and biosignatures. Habitability models are the foundation of planetary habitability science. The synergy between the methods used by ecologists and astrobiologists will help to integrate and expand our understanding of the habitability of Earth, the Solar System, and exoplanets.

Analytical Chemistry in Astrobiology

“…Developing analytical techniques to characterize other worlds and ultimately determine their habitability, or ability to support life, will be critical for future astrobiology missions as our search for life is constrained by our ability to find habitable environments. 16 Many different characteristics of a planetary body can indicate habitability, ranging from atmospheric composition to surface chemistries. Key indicators of habitability are a source of energy, the elements required by all known life 17 (CHNOPS), and the presence of liquid water.…”