The Star Light Simulator, right: Illuminated (right). It has a total of 25 channels and emits light between 365 nanometers (UV light) to 940 nanometers (infrared light). 

The ability of microorganisms to perform photosynthesis utilizing the infrared-dominated light emitted by the most prevalent type of Milky Way star has been experimentally proven for the first time by Italian researchers.

The Star Light Simulator’s findings, which were presented at the Euro planet Science Congress (EPSC) 2022, indicate that life may have evolved around stars other than our Sun, creating oxygen-rich planets that are livable by more advanced species.

The scientists developed an atmospheric simulator chamber that simulated a planetary environment and the light radiated by an M-dwarf for this experimental setup. According to Prof. Nicoletta La Rocca of the University of Padua, who oversaw the work, “we initially concentrated on cyanobacteria since they have amazing capacities to tolerate every condition on Earth, as well as a recognized ability to survive in near-infrared light.” “We expanded our tests to mosses and several forms of red and green microalgae once these adapted to the simulated environment.”

The microorganisms successfully demonstrated their ability to develop and photosynthesize under M-dwarf light in every experiment.

Prof. La Rocca said that one of the key requirements for an exoplanet to be deemed livable is liquid water because life as we know it depends on it. Oxygen is also essential for more advanced terrestrial life. Cyanobacteria that can-do photosynthesis was essential for oxidizing the atmosphere on Earth. The new experimental findings increase our understanding of possibly habitable regions and, consequently, where we might look for a planet supporting complex life.

Comparing M-dwarf stars to Sun-like stars for life and habitability: M-dwarf stars exhibit a substantially different spectrum of features than Sun-like stars, which has an effect on the possibility of life on planets orbiting those stars. 

ADDITIONAL INFORMATION

The findings have been submitted for publication in the special edition “Frontiers in Extremophiles: From Life at Edges on Earth to Space Exploration” of the open-access Life journal.