Summer Triangle

History

The term was popularized by the American author H. A. Rey and the British astronomer Patrick Moore in the 1950s. The name can be found in constellation guidebooks as far back as 1913. The Austrian astronomer Oswald Thomas described these stars as Grosses Dreieck (Great Triangle) in the late 1920s and Sommerliches Dreieck (Summerly Triangle) in 1934. The asterism was remarked upon by Joseph Johann von Littrow, who described it as the "conspicuous triangle" in the text of his atlas (1866), and Johann Elert Bode connected the stars in a map in a book in 1816, although without a label. These are the same stars recognized in the Chinese legend of The Cowherd and the Weaver Girl, a story dating back some 2,600 years, celebrated in the Qixi Festival. The stars also bear ceremonial significance in the related celebrations of Tanabata, Chilseok, and Thất Tịch, derived from Qixi. In the mid- to late-20th century, before inertial navigation systems and other electronic and mechanical equipment took their places in military aircraft, the United States Air Force navigators referred to this asterism as the "Navigator's Triangle".