Lunch talk by Tara Fetherolf (UCR)
Characterizing exoplanets first requires precise measurements of their host star’s properties. In addition to revealing possible companions, the shape and periodic nature of a star’s light curve can uncover important information about its intrinsic properties. Stellar pulsations and rotational modulations, for example, are inherently linked to a star’s evolutionary stage and thus can be used to infer stellar ages. The TESS spacecraft obtained high-precision space-based time-series photometry of nearly the entire sky during its primary mission, allowing for a large-scale study of stellar variability that is not sensitive to the diurnal limitation of ground-based surveys. We have developed a stellar variability catalog that includes ~50,000 stars that exhibit significant photometric variability on timescales of 0.01-13 days, which could be attributed to rotational modulations, stellar pulsations, or binarity. I will discuss the characteristics of the stars in our stellar variability catalog, which will serve as a valuable resource to the stellar astrophysics and exoplanet communities. The variability catalog will aid in 1) studying the characteristics of periodic variable stars; 2) understanding interactions between host star variability and planetary atmospheres; and 3) identifying exoplanets that are actually false positives caused by stellar variability.
