Stars · Star in Canis Major
Sirius
The brightest star in the night sky, and one of the nearest. Its name is Greek for “scorching”.
- Constellation
- Canis Major
- Designation
- α Canis Majoris
- Apparent magnitude
- -1.44 · 1st brightest star in the night sky
- Spectral class
- A0m
- Distance
- 8.6 light-years
- Position (J2000)
- RA 6h 45m · Dec −16° 43′
A white star, around 10,000 K, like Vega. About 1500× brighter than the faintest star the eye can see. The light you are seeing left in 2017.
History
Ancient Egypt’s calendar was anchored to the morning Sirius first reappeared before sunrise, in the season the Nile flooded. The Romans blamed its summer rising for the heat — the “dog days”.
Discovery
In 1844 Friedrich Bessel noticed Sirius wobbling as if circled by something unseen. In 1862 Alvan Clark saw it: Sirius B, the first white dwarf ever found.
Look for
Low in the sky Sirius flashes red, green and blue. That is our turbulent air splitting its light like a prism — the brighter the star, the more obvious.