Current opinions and trends in the search for extrasolar photosynthesis

Abstract

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.