NASA/NExSS Extraterrestrial Photosynthesis Workshop

A NASA Exoplanets System Science (NExSS) Workshop
May 15-17, 2026
Heidel House, Green Lake, Wisconsin, USA
Preceding AbSciCon 2026

About this workshop

The prospect of obtaining light reflected from planets outside of our Solar System (“exoplanets”) that might harbor life is a strong possibility within the next few decades. Such observations (“direct imaging” telescope technology) would provide spectral information on the entire atmospheric column to the planet’s surface.

Within our Solar System, the Early Earth represented eons with very different stages of coevolution of phototrophy with the atmosphere, while there has been speculation on the potential for photosynthesis in the clouds of Venus or with alternative metabolisms on Titan. Photosynthesis is a key process in the search for life on other planets, producing “biosignatures” that are both atmospheric and at the surface, in pigments and other organic molecules.

Studies to date on photosynthetic biosignatures have been dominated by oxygen and the vegetation red edge as produced by oxygenic photosynthesis, while anoxygenic photosynthesis could be the dominant form of photosynthesis on a planet prior to the evolution of oxygenic photosynthesis, as on the Archean Earth. In recent years, work has emerged internationally from diverse scientific disciplines to lend greater rigor to key questions about extraterrestrial photosynthesis adapted to other stars and planetary environments.

These studies have included co-authors from astronomy, biochemistry, biophysics, microbial ecology, evolutionary biology, geochemistry, and even solar energy. The interdisciplinary nature of these studies makes them particularly challenging for any single scientist to evaluate or for the astrobiology community to incorporate into decadal strategies. Thus, the search for extraterrestrial life would be propelled by a forum for discussion and feedback for many ideas that involve esoteric knowledge and understanding.

This workshop will bring researchers together to tackle questions such as:

• Can there be alternative primary photopigments to chlorophylls?
• How did the oxygen evolving complex (OEC) arise and can there be an alternative?
• Is there a low CO₂ limit for photosynthesis and respiration?
• How long can photosynthesis be viable over the life of a planet?
• Is there a long wavelength limit to oxygenic photosynthesis? Are there trade-offs at different wavelengths?
• What are the limits to the number of photosystems that can be strung in series to support electron transfers?
• What alternative methods to light harvesting and energy transduction developed in the field of artificial photosynthesis might be utilized naturally?
• What are the spectral signatures of the possible photopigments on planets orbiting other stars, and what are the near-term and long-term observatory capabilities that may be able to detect these signatures?

Registration and additional information https://nexss.info/extraterrestrial-photosynthesis-workshop/

Astrobiology,