Description
Until the late 1990s the rich Hyades and the sparse UMa clusters were the only coeval, comoving concentrations of stars known within 60 pc of Earth. Both are hundreds of millions of years old. Then beginning in the late 1990s the TW Hydrae Association, the Tucana/Horologium Association, the beta Pictoris Moving Group, and the AB Doradus Moving Group were identified within ~60pc of Earth, and the eta Chamaeleontis cluster was found at 97pc. These young groups (ages 8-50Myr), along with other nearby, young stars, will enable imaging and spectroscopic studies of the origin and early evolution of planetary systems.
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