Biosignatures & Paleobiology

Current Opinions And Trends In The Search For Extrasolar Photosynthesis

By Keith Cowing
Status Report
Science Direct
December 3, 2025
Filed under , , , , ,
Current Opinions And Trends In The Search For Extrasolar Photosynthesis
An example of a simulated spectrum for a Proterozoic Earth–like planet, in which no single feature dominates but absorption from numerous molecules is visible, including O2 and O3. The N2O features (shown in brown) appear at multiple wavelengths beyond 1 μm. Source: Tokadjian et al. (2024); image used unchanged under the CC BY 4.0 license. — Science Direct

The search for extrasolar photosynthetic life is one of the most important goals for modern astrobiology. Recent discoveries of cold brown dwarfs, as well as planets orbiting M-, G-, K-, and F-type main-sequence stars, have expanded opportunities to search for photosynthetic biosignatures within their habitable zones.

This comprehensive review synthesizes current knowledge and emerging trends in the field. The paper addresses stellar variability and how spectral energy distribution influences potential pigment evolution and photoprotective adaptations, whether photosynthetic life could exist on peculiar exoworlds with specific illumination and surface conditions, as well as observational strategies with current and future telescopes.

The goal of this work is to help researchers navigate the vast sea of knowledge by providing a strategic roadmap for prioritizing targets and interpreting potential biosignatures.

Astrobiology,

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

Follow on Twitter
MORE FROM Biosignatures & Paleobiology