summer triangle


August 8, 2022

Summer Triangle (English: Summer Triangle) or Summer Triangle Alpha Cygnus Deneb Alpha Aquila Altair Alpha Lyra: An asterism in the shape of a large elongated triangle drawn by connecting the three stars of Vega. Of the three stars, Vega and Altair are "Orihime" and "Hikoboshi" in the Tanabata legend.

Good Staring Season

In the mid-latitude regions of the Northern Hemisphere, it begins to be visible in the early morning of spring and remains visible until the evening of November. It can be seen well during the summer, but in Japan, the summer triangle has just risen during the Tanabata season (around 8:00-10:00 pm). It's been raining a lot and I can't see well. It can be seen better in early August, which corresponds to the old Tanabata and the late Tanabata. In September, it reaches almost the zenith, and if the conditions are good with few street lights, you can see the Milky Way crossing the sky. In the Southern Hemisphere, it can be seen upside down in the low sky during winter, making it suitable for being called the "Northern Triangle".



The name "Summer Triangle" was popularized in the 1950s by British astronomy popularist Sir Patrick Moore. However, it was not invented by Moore, but was described in the 1920s by the Austrian astronomer Oswald Thomas as "Grosses Dreieck" (German for "big triangle"). In 1934, he described it as "Sommerliches Dreieck" (German for "Summer Triangle"). Earlier, the Austrian astronomer Joseph Johann von Littrow described it as "a conspicuous triangle" in the text of his star atlas published in 1866. German astronomer Johann Bode was the first to connect the three stars in a star chart in his book published in 1816. However, while Bode connected the stars, he did not give them any name. In the second edition of the Flamsteed Atlas, published in Paris in 1776 by the French orb maker Jean Nicolas Fortin, only Vega and Altair are connected out of the three stars. At the time, Deneb did not rank among the "brightest clusters of stars", i.e. first magnitude stars. In "Ptolemy's Star Chart" in "Almagest", Altair was also a second-magnitude star.


So far, it is not known who first called it "summer triangle" or "summer triangle" in Japan. Hoei Nojiri, an English scholar and astronomical folklorist, used the name 'Summer Triangle' in his 1947 book. Akira Fujii, who is known for his prolific writing of astronomical books for the general public, touched on the ``Great Summer Triangle'' in his first book in 1969 (Showa 44). The Great Triangle” is actively used as a landmark for searching for summer constellations. In the Japanese astronomical magazine for the general public, "Tenmon and Meteorology", the predecessor of "Monthly Tenmon", introduced it as "The Summer Triangle" in the August 1965 issue. In the August 1969 issue of "Monthly Tenmon Guide," the description of the "Great Summer Triangle" appeared for the first time. In the later issue Hoshi no Techo, which was first published in 1978, from the first issue (summer issue), "Summer