Photosynthesis on Exoplanets and Exomoons from Reflected Light

Abstract

Photosynthesis offers a convenient means of sustaining biospheres. We quantify the constraints for photosynthesis to be functional on the permanent nightside of tidally locked rocky exoplanets via reflected light from their exomoons. We show that the exomoons must be at least half the size of Earth's moon in order for conventional oxygenic photosynthesis to operate. This scenario of photosynthesis is unlikely for exoplanets around late-type M-dwarfs due to the low likelihood of large exomoons and their orbital instability over long timescales. Subsequently, we investigate the prospects for photosynthesis on habitable exomoons via reflected light from the giant planets that they orbit. Our analysis indicates that such photosynthetic biospheres are potentially sustainable on these moons except those around late-type M-dwarfs. We conclude our analysis by delineating certain physiological and biochemical features of photosynthesis and other carbon fixation pathways, and the likelihood of their evolution on habitable planets and moons.

arXiv commentAccepted for publication in the International Journal of Astrobiology; 21 pages; 4 figures

References in corpus (35)

• Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1
• A terrestrial planet candidate in a temperate orbit around Proxima Centauri
• Planetary Candidates Observed by Kepler, III: Analysis of the First 16 Months of Data
• The Occurrence and Architecture of Exoplanetary Systems
• Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life
• Vegetation's Red Edge: A Possible Spectroscopic Biosignature of Extraterrestrial Plants
• Spectral signatures of photosynthesis I: Review of Earth organisms
• Exoplanet Biosignatures: Understanding Oxygen as a Biosignature in the Context of Its Environment
• Spectral signatures of photosynthesis II: coevolution with other stars and the atmosphere on extrasolar worlds
• Tidal Locking of Habitable Exoplanets
• Atmospheric escape from the TRAPPIST-1 planets and implications for habitability
• Evidence for a Large Exomoon Orbiting Kepler-1625b
• Is Proxima Centauri b habitable? -- A study of atmospheric loss
• Formation, Habitability, and Detection of Extrasolar Moons
• Exomoon habitability constrained by energy flux and orbital stability
• A more comprehensive habitable zone for finding life on other planets
• No Evidence for Lunar Transit in New Analysis of Hubble Space Telescope Observations of the Kepler-1625 System
• The formation of mini-Neptunes
• Runaway greenhouse effect on exomoons due to irradiation from hot, young giant planets
• Physical constraints for the evolution of life on exoplanets
• Viscoelastic Models of Tidally Heated Exomoons
• Early evolution of purple retinal pigments on Earth and implications for exoplanet biosignatures
• Light and Life: Exotic Photosynthesis in Binary Star Systems
• Physical constraints on the likelihood of life on exoplanets
• Dependence of Biological Activity on the Surface Water Fraction of Planets
• Surface Flux Patterns on Planets in Circumbinary Systems, and Potential for Photosynthesis
• Exomoon Habitability and Tidal Evolution in Low-Mass Star Systems
• Photosynthesis on habitable planets around low-mass stars
• Is Life Most Likely Around Sun-like Stars?
• The Effect of Multiple Heat Sources on Exomoon Habitable Zones
• Exoplanets Torqued by the Combined Tides of a Moon and Parent Star
• Worlds Without Moons: Exomoon Constraints for Compact Planetary Systems
• Exomoon Climate Models with the Carbonate-Silicate Cycle and Viscoelastic Tidal Heating
• Brown Dwarf Atmospheres as the Potentially Most Detectable and Abundant Sites for Life
• Optimal Target Stars in the Search for Life

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• Prospects for Life on Temperate Planets Around Brown Dwarfs
• Characteristics of aquatic biospheres on temperate planets around Sun-like stars and M-dwarfs
• The effect of post-Newtonian spin precessions on the evolution of exomoons' obliquity
• The Most Common Habitable Planets III -- Modeling Temperature Forcing and Surface Conditions on Rocky Exoplanets and Exomoons