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15 Starry Facts About the Sirius Star You Definitely Didn't Know

15 Interesting Facts About the Sirius Star You May Not Know
Sirius belongs to the Canis Major constellation and is the brightest star visible from the Earth at night. Take a look at some facts about the Sirius star that explain its extremely bright appearance.
Vibhav Gaonkar
Last Updated: Jun 2, 2018
Sirius Black
It is believed that Sirius Black from Harry Potter who has the unique ability to transform into a black dog could have been inspired by the 'Sirius B' star.
The name Sirius is coined from the Greek term Seirios, which means 'glowing'. Sirius is also referred to as the 'Dog Star' with reference to the constellation it belongs to (Canis Major). Given below are some statistics that determine Sirius's location, size, temperature, and distance from the Earth.
Constellation Canis Major
Distance from Earth 8.611 Light Years
Temperature 9,940 K
Mass 2.02 Solar Mass
Radius 1,190,000 km
Magnitude -1.46

Now go through some interesting facts about this distinct star.
Sirius Star Facts
The Sirius Binary System
Sirius binary system
Sirius 'B'
Sirius B
Location of Sirius in Canis Major
Location of Sirius in Canis major
The Canis Major Constellation
Canis major constellation
★ Sirius is a binary star system consisting of the main star Sirius A, and its small dwarf companion Sirius B.
★ This binary star system is approximately 300 million years old, and was previously composed of two huge bluish stars that were almost of equal size. Out of these, one used up all its nuclear fuel and shrunk to a very tiny size (Sirius B).
★ The Egyptians during the Middle Kingdom era (2055 - 1650 BCE) used a calendar based on the helical rising of Sirius. On the other hand, the Polynesians considered it as a crucial star for navigation.
★ Sirius B is hotter than Sirius A with a temperature of 25,200 K. However, as the star has burned all its fuel, it doesn't have any internal heat source and would eventually cool down after an approximate 2 to 3 billion years.
★ It is observed that the Sirius system is gradually moving closer to the Solar System, which would result in its increased brightness in the next 60,000 years.
★ Sirius has a brightness that is 20 times more than the Sun, and also a temperature exceeding the Sun's by approximately 4000 K. Its size is also around 40% larger than the Sun.
★ The fact that Sirius had a companion was first predicted in 1844, and was confirmed two decades later in 1862 by Alvan Graham Clark. This dwarf star or Sirius B was affectionately called 'the pup'.
★ Sirius is so bright that it can even be observed under stark daylight with the naked eye, provided the sky is clear, the observer is at a high altitude, and the Sun is at the horizon.
★ The star was of immense importance in the ancient times. I was worshiped and offered sacrifices with the intention that it would bring good fortune. Coins retrieved from 3rd century BCE were embossed with pictures of dogs or stars emitting rays, which clearly depict the importance of Sirius.
★ The Romans sacrificed a dog each year during summer to impress the goddess Robigo to prevent the star's emanations from causing wheat rust. The star's appearance in the morning sky indicated the rise of summer in Greece, and the onset of winter in Polynesia.
★ In the Serer religion originating in Senegal, Mauritania, and Gambia, Sirius is referred to as Yoonir, and is considered one of the most sacred stars in the religion. It is used to forecast rainfall so that the Serer farmers can begin planting seeds. A similar belief of Sirius as the rain-maker exists in the Persian mythology too.
★ The Canis constellation is sometimes referred to as the dog of Orion, as the belt of Orion is seen pointing towards the Sirius star.
★ An engine produced by Mitsubishi Motors somewhere in the 1980s was named after the star as Mitsubishi Sirius engine.
★ Sirius is also one of the 27 stars on the Brazil flag, and depicts the state of Mato Grosso.
★ It is speculated that there is also a third star that exists in the system, but there is no evidence to confirm this.
If you wish to spot Sirius, observe the southern sky, preferably on a late winter evening, and you'll instantly see it slightly towards the southeast. You can also locate it using these co-ordinates, 06h 45m 08.9173s, -16 42'58.017".