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One of the prime stars of summer continues to dazzle in the autumn sky. Vega is quite high in the west at nightfall. It’s the brightest member of the Summer Triangle.
Vega is known by many names. One of the most important is HD 172167. That’s its listing in the Henry Draper Catalog. The first volume was published a century ago.
People have been compiling star catalogs for a long time. One of the earliest was done more than 2,000 years ago. It recorded the positions of more than a thousand stars. An early modern catalog was compiled by Johann Bayer, in 1603. In it, Vega is known as Alpha Lyrae — the leading light of the constellation Lyra.
Work on the Henry Draper catalog dates to 1872. That’s when Draper, an amateur astronomer, took the first photograph of the spectrum of a star. It recorded the “fingerprint” of Vega.
When Draper died, Harvard College Observatory took over the job of recording spectra. A first catalog was published in 1890, with a new way of classifying stars.
By 1918, Annie Jump Cannon had led the creation of a new catalog, with 225,000 stars. In it, she reworked the way stars were classified. Both the system and the catalog are still in use today.
Astronomers have compiled many more catalogs since then. The largest was released this year. It consists of observations made by the Gaia spacecraft, which is measuring stellar distances. The catalog lists a record 1.7 billion stars.
Script by Damond Benningfield