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a classification of stars based on the characteristic spectral absorption lines and bands of the chemical elements present
C20: named after the observatory at
Massachusetts, where it was prepared and published as part of
The Henry Draper Catalogue
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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