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تسجيل مستخدم جديدA Pre-Gaia Census of Nearby Stellar Groups
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Eric E. Mamajek
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The nearest, youngest groups of stars to the Sun provide important samples of age-dated stars for studying circumstellar disk evolution, imaged exoplanets, and brown dwarfs. I briefly comment on the status of the known stellar groups within 100 pc: $beta$ Pic, AB Dor, UMa, Car-Near, Tuc-Hor and $beta$ Tuc nucleus, Hyades, Col, TW Hya, Car, Coma Ber, 32 Ori, $eta$ Cha, and $chi^1$ For. I also discuss some poorly characterized groups and non-groups. Grades for 2015 of Pass, Satisfactory, or Fail are assigned to the groups for the purposes of age-dating stars and brown dwarfs. I speculate that Tuc-Hor could have provided a supernova ~60 pc away ~2.2 Myr ago which showered the Earth with traces of 60Fe-bearing dust.
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