The Dog Star, Sirius isn’t just one star but has a companion star known as Sirius B which revolves around Sirius A varying in distance between about 8 astronomical units and 31 astronomical units. An astronomical unit ,AU, is the mean distance between the Sun and Earth. Sirius Alpha is the brighter of the two with Sirius Beta only visible through a telescope. Sirius B is a white dwarf star. The binary star system is one of our closest stars being only 8.6 light years away.
The Dog star has a very long observational history beginning before the Egyptians and continuing till today. There are multiple references to Sirius, commonly known as the Dog Star, in almost all cultures and strangely enough they all refer to Sirius as some form of canine. Cultures from South America, North America and even China. Very amazing. You have almost certainly heard of the “Dog days of summer” which is a reference to the rising of the Dog Star just before sunrise at the beginning of summer. Now you know where the term comes from, the Egyptians.
Christians practice “Dogma” which is a reference to the Dog Star. Priests wear a dog collar, once again a reference to the Dog Star and of course if you were to spell Dog backwards you would in fact be writing the name of God.