Presentation #142.03 in the session SETI and Planetary Habitability — iPoster Session.
Whether M dwarfs are able to host life-bearing planets is an open question owing to high levels of stellar X-Ray and UV emission and close-in habitable zones. Conversely, the low levels of near-UV emissions at quiescent levels of M dwarfs may make it challenging for abiogenesis (the origin of life) to occur. We considered whether flares from the ~20 Myr old M dwarf AU Mic have the potential to raise the stellar near-UV flux to a level at which prebiotic chemical pathways are triggered over the wavelength range 200-280 nm. We obtained near-UV spectroscopy of AU Mic using the Neil Gehrels Swift Observatory’s (Swift) UltraViolet and Optical Telescope’s (UVOT) grism mode. We analyzed multiple flares, measuring their energy, duration, and amplitude relative to the abiogenesis threshold, over the course of a 52 kilosecond pilot study. Our results provide a window into the elevated near-UV flux with which AU Mic regularly irradiates its planetary system. This work provides constraints on the UV flux that planets orbiting young stars experience, with these results serving as a benchmark for inferring whether young M dwarf stellar activity can help catalyze abiogenic reactions on planetary surfaces. We have shown that Swift is able to spectroscopically monitor the flares in the near-UV, observations that are critical for determining if abiogenesis can proceed on exoplanets orbiting low-mass stars.