Towards comparative atmospheric characterization using multiplanetary systems from TESS

Exoplanets transiting bright stars are amenable to precise mass determination, opening up the potential for their detailed atmospheric characterization. However, exoplanets evolve under the influence of host stars with a broad range of ages and initial properties. This challenges conclusions regarding the direct relationship between the inferred atmospheric characteristics and the planetary properties such as radius, mass, and equilibrium temperature. Systems with multiple planets transiting the same bright star allow these investigations to be made while controlling for the type of the host star and its activity history. The Transiting Exoplanet Survey Satellite (TESS) has discovered several such opportune systems during the nominal mission, including a quartet of small exoplanets transiting a bright, Sun-like (G3V) star, TOI 1233. The broad range of radii and equilibrium temperatures spanned by these exoplanets enable comprehensive sampling of different atmospheric conditions and will be interesting targets for studies of atmospheric loss and composition via transmission spectroscopy.