PROSPECTS FOR CHARACTERIZING THE ATMOSPHERE OF PROXIMA CENTAURI b
Laura Kreidberg & Abraham Loeb
The newly detected Earth-mass planet in the habitable zone of Proxima Centauri could potentially host life—if it
has an atmosphere that supports surface liquid water. We show that thermal phase curve observations with the
James Webb Space Telescope ( JWST) from 5–12 μm can be used to test for the existence of such an atmosphere.
We predict the thermal variation for a bare rock versus a planet with 35% heat redistribution to the nightside and
show that a JWST phase curve measurement can distinguish between these cases at 4σ confidence, assuming
photon-limited precision. We also consider the case of an Earth-like atmosphere, and find that the 9.8 μm ozone
band could be detected with longer integration times (a few months). We conclude that JWST observations have
the potential to put the first constraints on the possibility of life around the the solar system’s nearest star.
Reference: Kreidberg, L. & Loeb, A. (2016 November 15). Prospects for Characterizing the Atmosphere of Proxima Centauri b. The Astrophysical Journal Letters, 832(1). doi:10.3847/2041-8205/832/1/L12 © AAS. Reproduced with permission.