Photosynthesis on habitable planets around low-mass stars. Issue 4 (27th March 2019)

• Record Type: Journal Article
• Authors: Lingam, Manasvi; Loeb, Abraham
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 485:Issue 4(2019)
• Page Start: 5924
• Page End: 5928
• Publication Date: 2019-03-27
• Subjects: extraterrestrial intelligence -- astrobiology -- stars: low-mass; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz847
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We show that planets around M-dwarfs with M ⋆ ≲ 0.2 M⊙ may not receive enough photons in the photosynthetically active range of 400–750 nm to sustain Earth-like biospheres. As a result of the lower biological productivity, it is likely that biotic molecular oxygen would not build-up to detectable levels in the atmospheres of habitable planets orbiting low-mass stars, consistent with prior work by Lehmer et al. We also estimate the minimum flaring rate for sustaining biospheres with Earth-like productivity and permitting the build-up of atmospheric oxygen, and find that the overwhelming majority of M-dwarfs are unlikely to exceed this threshold.