0 Assigned ID: 3056 ----- Attempting Submission 1 (Thu Mar 24 20:43:57 GMT 2022) ----- HST Phase I Proposal 3056 successfully submitted. Receipt: # 3056-1 ----- Attempting Submission 2 (Fri Mar 25 18:37:53 GMT 2022) ----- HST Phase I Proposal 3056 successfully submitted. Receipt: # 3056-2 ----- Attempting Submission 3 (Fri Mar 25 18:40:40 GMT 2022) ----- HST Phase I Proposal 3056 successfully submitted. Receipt: # 3056-3 ----- Attempting Submission 4 (Fri Mar 25 20:52:17 GMT 2022) ----- We aim to establish a transformational approach to age dating Sun-like main sequence stars with ages greater than roughly 1 Gyr. Verification of the proposed methodology would usher in the ability to obtain accurate age estimates for a large fraction of main sequence stars in the solar neighborhood and many beyond; the scientific applications of such a capability are myriad and include stellar astrophysics, Galactic archaeology, and exoplanet system studies. We will synthesize archival HST and in some cases IUE data to explore age-activity trends for ultraviolet emission. Previous works indicate that chromospheric ultraviolet MgII emission experiences a dramatic drop-off with stellar age for ages greater than roughly 1 Gyr; through this work we will confirm and better characterize this drop-off with stars having well-measured ages. We will assess how robust a MgII age-activity relation is for stars older than roughly 1 Gyr and with what precision it allows one to estimate a stellar age. Carl Melis (PI, UC San Diego) completed his Ph.D. in Astronomy at UC Los Angeles in 2009 where he developed expertise in stellar astrophysics and planetary system formation and evolution. He has since been a post-doctoral researcher and now member of the research faculty at UC San Diego conducting a variety of projects related to stellar astrophysics, including characterizing the ages of stars of interest (e.g., see Melis et al. 2021, ApJ 923, 90). PI Melis will be the lead on this project, ensuring all tasks are being completed and publications prepared. He plans to lead undergraduate students in conducting this work and may support them with any awarded funds. The PI will lead students in preparing papers and submitting them, or if need be take the lead on them himself. Stellar Physics and Stellar Types Stellar Populations and the Interstellar Medium 0 Regular false false false false false false SUPPORTED