Our only current example of a biosphere is flamboyantly alive and exhibits big chemical signposts to that effect. While the search for such clearly dynamic life-bearing planets is an important target for exoplanet biosignature searches, here in our own Solar System Earth seems to be the only planet in this category. However, we harbor hopes that more cryptic biospheres may exist on other bodies, or rather within other bodies relatively close to home like Mars, Europa, or Enceladus. The living templates we have here on Earth to shape our efforts to detect such “hidden” biospheres are the subsurface microbial communities of the rock fractures of seafloors and land masses, caves, and aquifers. I will present lessons learned based on 25 years of my own team’s work in these subterrains and insights from other salient investigators. Are there ways that such cryptic biospheres might be detectable from afar?
Getting Under Europa’s Skin
Tracing Formation and Evolution of Outer Solar System Bodies Through Stable Isotopes and Noble Gas Abundances
Photosynthesis, a Planetary Revolution
Xenon: King of the Gases
NAI
