A Spectroscopic Analysis of the Ultraviolet Evolution of K Stars

Knowing the UV emission of a star during a planet's formation and evolution is critical in determining if that planet is potentially habitable and if any biosignatures could be detected, as UV radiation can severely change or destroy a planet's atmosphere. Current efforts for finding a potentially habitable planet lie with M stars, yet K stars may offer more habitable conditions due to decreased stellar activity and more distant and wider habitable zones. We observed a sample of K stars in the near-UV and far-UV at three representative ages using the Cosmic Origins Spectrograph on the Hubble Space Telescope (HST) to spectroscopically analyze the UV evolution of K stars. Here, we present the first results of this HST program. We will discuss the evolution of both the continuum and line emission from K stars from ages 40 Myr to ~Gyrs, representing key periods in planetary atmospheric formation.