About this Research Topic
An integrative approach is required to link the efforts of microbiologists exploring the origins, evolution, and limits of life to the work of geologists exploring both planetary conditions (past and present) and preservation of biosignatures in the geological record. These efforts must also be linked to astronomers and astrophysicists studying the origins and evolution of the Universe and the detection of exoplanets, and to chemists studying the transition from the pre-biotic world.
We are at the cusp of an age of discovery for potential life on other planetary bodies. Efforts are being made to couple exoplanet discovery, the study of asteroids and comets, ground-based analyses of recovered meteorites with analog planetary-scale biosignature detection. Outer space along with ground-based simulating facilities provides a research tool for studying life in the Universe. Series of microbial exposure experiments have been successfully performed on board and outside of the International Space Station under the environmental conditions of low Earth orbit or mimicking planetary constraints. Exposure experiments at ground-based simulating facilities have enabled the investigation of the effects of space-related parameters on microbial survival and adaptation capacities.
Being a few steps away from retrieving and returning the first samples from the surface of Mars, we have already gained extensive knowledge from the field, laboratory, and space exposure experiments. This should enable a comprehensive characterization of the first Mars returned samples in terms of potential exobiology.
Revealing unknown boundaries for prokaryotic life under the multiple extremes is a prerequisite to our efforts to understand the extent of biology on Earth, and to discover its wider presence in the Universe.
In this Research Topic, we intend to explore the interactions between the biological, geological, hydrological, and atmospheric elements in the Universe. We seek to address the impact of planetary conditions on the evolution of microorganisms, molecular mechanisms driving the limits of life under different physiochemical regimes, and traces of life that can be detected as small- (fossils) or large-scale (atmospheric alteration) changes in the physiochemical conditions of Earth and beyond.
Specifically, we invite researchers from all areas of astrobiology (biology, chemistry, physics, geology, and astronomy) to submit their work in the following areas:
1) Origins and evolution of life-related to planetary conditions
2) Co-evolution of biosphere, geosphere, hydrosphere, and atmosphere
3) Survival of biological molecules and/or microorganisms (laboratory/field-based studies in extreme and analog environments, space-based exposure and ground-based simulation experiments)
4) Refining the definition of the "boundaries of life"
5) Preservation and detection of biosignatures of life
6) Development of life detection missions and technologies
The Topic Editors would like to acknowledge Dr. Yuko Kawaguchi for her contribution in designing and organizing this editorial project.
Keywords: Biosignatures, Habitability, Planets, Extremophiles, Exobiology/Astrobiology
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.