Abstract

Poster - Plenary

Assessing biosignature gas stability in exoplanet atmospheres around M dwarfs

Pao Ying Heng
University of Aberdeen

The stability of potential biosignature gases plays a key role in determining their detectability through transmission spectroscopy. Stellar activity and atmospheric conditions may limit how long such compounds persist in an exoplanet’s atmosphere. This work assesses whether candidate biosignature gases - such as dimethyl sulfide - can persist long enough to reach detectable levels in the atmospheres of transiting exoplanets around M dwarfs. Representative stellar spectra are analysed alongside molecular absorption cross-section data to assess susceptibility to photodissociation and estimate potential atmospheric lifetimes. The results are intended to support biosignature interpretation by accounting for whether candidate gases can realistically persist in exoplanet atmospheres under M-dwarf conditions.