A Hipparcos Census of the Nearby OB Associations (iopscience.iop.org)A comprehensive census of the stellar content of the OB associations within 1 kpc from the Sun is presented, based on Hipparcos positions, proper motions, and parallaxes. It is a key part of a long-term project to study the formation, structure, and evolution of nearby young stellar groups and related star-forming regions. OB associations are unbound “moving groups,” which can be detected kinematically because of their small internal velocity dispersion. The nearby associations have a large extent on the sky, which traditionally has limited astrometric membership determination to bright stars (V ≲ 6 mag), with spectral types earlier than ∼B5. The Hipparcos measurements allow a major improvement in this situation.
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Helen Keller (Wikipedia)Helen Adams Keller (June 27, 1880 – June 1, 1968) was an American author, disability rights advocate, political activist and lecturer. Born in West Tuscumbia, Alabama, she lost her sight and her hearing after a bout of illness when she was 19 months old. She then communicated primarily using home signs until the age of seven, when she met her first teacher and life-long companion Anne Sullivan. Sullivan taught Keller language, including reading and writing. After an education at both specialist and mainstream schools, Keller attended Radcliffe College of Harvard University and became the first deafblind person in the United States to earn a Bachelor of Arts degree.