With Lynne Hillenbrand and David Soderblom, we used the Galaxy Evolution Explorer (GALEX) to study young stars between 10 and 800 million years old. Young stars show stronger chromospheric activity than older stars. Since stellar chromospheres produce significant ultraviolet emission, young stars tend to be brighter in the ultraviolet than older stars of the same optical color. The high sensitivity of GALEX to ultraviolet emission allowed us to calibrate for a UV activity-age relation for the first time, enabling future researchers to quickly estimate the activity level of any star with GALEX coverage.
"Stellar Activity in the Broadband Ultraviolet", Findeisen, Krzysztof; Hillenbrand, Lynne; Soderblom, David (2010), The Astronomical Journal, 142, 23 ADS
"Ultraviolet-selected Field and Pre-main-sequence Stars Toward Taurus and Upper Scorpius", Findeisen, Krzysztof; Hillenbrand, Lynne (2010), The Astronomical Journal, 139, 1338 ADS