"The Summer Triangle is an astronomical asterism involving an imaginary triangle drawn on the northern hemisphere's celestial sphere, with its defining vertices at Altair, Deneb, and Vega, the brightest stars in the three constellations of Aquila, Cygnus, and Lyra, respectively. ...
Near midnight the Summer Triangle lies virtually overhead at mid-northern latitudes during the summer months, but can also be seen during spring in the early morning to the East. In the autumn the summer triangle is visible in the evening to the West well until November. From the southern hemisphere it appears upside down and low in the sky during the winter months." [Summer Triangle. Wikipedia]
This example was redesigned from the Wikimedia Commons file: Summer triangle network.jpg. [commons.wikimedia.org/wiki/File:Summer_triangle_network.jpg]
This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication. [creativecommons.org/publicdomain/zero/1.0/deed.en]
The astronomical diagram example "Summer triangle network" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Astronomy solution from the Science and Education area of ConceptDraw Solution Park. www.conceptdraw.com/solution-park/science-education-astronomy