University of Edinburgh

BSL Astronomy Glossary - summer triangle - definition

Definition: In the night sky, during the summer months, the Summer Triangle is clearly visible from the northern hemisphere, looking to the south. It is made up of three bright stars, each of which is the brightest star in three different constellations. The first star, Deneb, belongs to the constellation of the swan, Cygnus; the second star is Vega in the constellation of Lyra and the third star is Altair, in the constellation of Aquila, the Eagle