# TESS Program G09082

Title: Ophion: Fossil Population Or False Alarm?

PI: Bouma, Luke - California Institute Of Technology

Type: SMALL

Summary: We propose a distance- and flux-limited variability census for stars with T<16 and d<500 pc in the Cycle 9 TESS full-frame images. Our primary goal is to test whether the newly reported Ophion population, located in a longstanding gap in TESS coverage north-east of the Galactic center, is a real pre-main sequence population. The key test is whether the Ophion region is unusually rich in young stars relative to analogous volumes around other Sco-Cen subgroups. We will extract and release light curves, measure rotation periods, and combine rotational youth with Gaia-based age diagnostics. The resulting public dataset will also support broad community studies of stellar variability and nearby star formation.