Facts about Sirius
- 08
Sirius A and its white dwarf companion are moving toward our solar system at 5.5 kilometers per second, and in approximately 296,000 years Sirius will reach its closest distance of 7.8 light-years from Earth.
- 07
Sirius A's surface temperature reaches approximately 10,000 Kelvin, making it roughly twice as hot as our Sun's 5,778 Kelvin surface.
- 06
Approximately 25,000 times brighter than our Sun in absolute luminosity, Sirius A is a main-sequence star with twice the Sun's mass and 1.71 times its radius.
- 05
In 1862, Alvan Graham Clark discovered Sirius B while testing a new telescope, making it the first white dwarf ever identified by astronomers.
- 04
The binary system of Sirius completes one full orbital cycle every 50.09 years, with Sirius B reaching its closest approach to Sirius A in 2025.
- 03
Ancient Egyptian astronomers identified Sirius around 3285 BCE as the herald of the Nile's annual flooding, naming it Sothis and using its heliacal rising to mark their new year.
- 02
Sirius B, the white dwarf companion star orbiting Sirius A, has a mass equal to our Sun but compressed into an Earth-sized sphere with a density of one million times that of water.
- 01
At approximately 8.6 light-years from Earth, Sirius is the brightest star in our night sky with an apparent magnitude of minus 1.46.