Which three stars is the summer triangle?

The summer triangle is three famous bright stars in the summer night sky: Vega, Altair and Tianjin IV.

The summer triangle refers to the triangle composed of Vega Lyra, Cygnus Tianjin IV and Altair Eagle in the southeast of summer. The west of the triangle is the silver Vega, the east is the four stars in Tianjin and the southeast is the Altair. You can also find a bright galaxy in this triangle.

You can only see the Summer Triangle on cloudy days in summer nights. Summer Triangle is accompanied by a well-known love story, which is the easiest to remember and identify. Generally, as long as one main star and two other companion stars are found, this main star is the cowherd. What's more, the four stars of daughter, cowherd, son and weaver girl are almost in a straight line, which is very conspicuous.

introduction.

Vega is the fifth brightest star in the northern hemisphere, second only to arcturus. Like Sirius and arcturus, it is one of the brightest stars near the sun, about 25 light years away from the Earth. In summer in the northern hemisphere, most observers can see Vega with naked eyes near the zenith. Because of precession, Vega was the polar star in the northern hemisphere around 12 BC, and will become the north star again in 14 AD, when the declination will reach+86 14'.

Vega is the first star photographed by photography and recorded by spectrum after the sun. It was one of the first stars whose distance was estimated by parallax measurement. It was once the calibration baseline for measuring luminosity and brightness scale and one of the stars used by UBV photometry system to define the average value. In the 19th century, astronomer Jensen designed the concept of apparent magnitude, and defined Vega as the -magnitude star in each band, which is called "Vega magnitude".