Letters of the Astrophysical Journal
The early history of the solar wind has remained largely a mystery due to the difficulty of detecting winds around young stars that can serve as analogs for the young Sun. Here we report on the detection of a wind from the 500 Myr old solar analog π1 UMa (G1.5 V), using spectroscopic observations from the Hubble Space Telescope. We detect H I Lyα absorption from the interaction region between the stellar wind and interstellar medium, i.e., the stellar astrosphere. With the assistance of hydrodynamic models of the π1 UMa astrosphere, we infer a wind only half as strong as the solar wind for this star. This suggests that the Sun and solar-like stars do not have particularly strong coronal winds in their youth.Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-12596.
Wood, Brian E.; Müller, Hans-Reinhard; Redfield, Seth; and Edelman, Eric, "Evidence for a Weak Wind from the Young Sun" (2014). Open Dartmouth: Faculty Open Access Articles. 1771.