Sirius is a two star system 8.6 light years from Earth. It consists of the main sequence star Sirius A and its small white dwarf compand their fuel and shed their outer layers.
Sirius B ision Sirius B. White dwarfs are the core remains of stars that have exhauste the closest white dwarf star to Earth. The force of gravity on Sirius B is 350,000 stronger than on Earth, meaning 3 grams of matter (roughly a sugar cube) would weigh 1,000 kilos (2,200 pounds)!
Sirius A is known as a main sequence star, meaning like the sun it produces energy by fusing hydrogen atoms in its core. Sirius is the brightest star in the night sky and the nearest that can be seen without the aid of a telescope.
Sirius B has a highly elliptical orbit around its larger companion. The derivation of the name Sirius is from the ancient Greek word for glowing, the star was also known to ancient Egyptians 4,000 years ago.
Sirius A has a radius of 740,000 miles (1.2 million km), which is 71% larger than the radius of the sun, Sirius B has a radius of only 3,650 miles (5,900 km) which makes it slightly smaller than planet Earth!
Sirius A has twice the mass of our sun, despite Sirius B being similar in size to Earth it has almost the same mass as the sun, making it an incredibly dense object.
Also Known As: Alpha Canis Major, the Dog Star
Distance From Earth: 8.6 light years
Constellation: Canis Major
Sirius A Star Type: Class A – Main sequence white star
Sirius B Star Type: White Dwarf
Sirius A Mass: 2.02 x Sun
Sirius B Mass: 0.98 x Sun
Sirius A Luminosity: 25 x Sun
Sirius B Luminosity: 3% of Sun
Sirius A Diameter: Approx 1.5 million miles (2.4 million km) – 171% x Sun
Sirius B Diameter: Approx 7,300 miles (11,800 km) – 92% x Earth
Sirius A Temperature: Approx 10,000C (18,000F)
Sirius B Temperature: Approx 25,000C (45,000F)
Age of System: Approx 240 million years old