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Sirius is known as the __________ star.

dog. Originally, the name only referred to the star itself, not the entire constellation as today.

Sirius resides in what constellation?

Canis Major. Canis Major is one of Orion's hunting dogs, Canis Minor is the other. Ursa Major and Minor are the larger and lesser bear.

Sirius is part of the winter triangle.

t. The winter triangle consists of Sirius in Canis Major, Betelguese in Orion, and Procyon in Canis Minor. Sirius at 8.7 light years distant, and Procyon, about 11.4 light years distant, are relatively close. Betelguese is about 600 light years distant from us and is a red giant star and about 1,000 times larger then our Sun.

Sirius rotates quicker than our Sun.

t. Sirius rotates in just 5.5 days, compared to our Sun's rotation of about 30 days.

Sirius is about 8.6 light years distant, making it the ___________ closest star system currently known to our Sun.

fifth. Only the Alpha Centauri system at 4.3 light years, Barnard's star at 6.0 light years, Wolf 359 at 7.7 light years, and the Luyten 726-8a&b system at 8.4 light years are known to be closer.

Sirius (A), the star we see in the sky, has a companion star (Sirius B) which is actually hotter than Sirius A.

t. Sirius B is a white dwarf star at 24,800 degrees Kelvin, while Sirius A is radiating at about 10,000 degrees Kelvin. Our Sun radiates at around 6,000 degrees Kelvin.

The name "Sirius" comes from the Greek word for?

Searing. It is also from another Greek word - Scorcher.

Sirius B was the second star identified as a white dwarf star.

f. Subrahmanyan Chandrasekhar ideintifed Sirius B as a white dwarf star in 1930, making it the first such star identified. Sirius B was actually discovered in 1862 by Alvan Graham Clark, the famous telescope maker. Sirius B is sometimes referred to as the "Pup". A white dwarf star is a "dying" star that is about the size of the Earth.

Sirius A and Sirius B are separated by about the same distance as the...

Sun and Uranus. Sirius A and B are separated by about 20 AU, about the same as the Sun-Uranus. One AU (astronomical unit) is the average distance between the Sun and Earth, about 93 million miles.

Sirius is the brightest star in Earth's night sky.

t. Only our Sun, Moon, Venus, Jupiter and Mars (at opposition), and the occasional extra bright comet, are brighter objects in our sky. Of course, a supernova could outshine even our Sun!