Sirius B
White dwarf (DA2) · Alpha Canis Majoris B
Nearest white dwarf to Earth
The burnt-out core of a star once more massive than Sirius itself, Sirius B holds a little more than the Sun's mass in a sphere about the size of Earth, which makes it the nearest white dwarf to us. Its existence was inferred in 1844 from a wobble in Sirius A's motion and confirmed in 1862, when Alvan Graham Clark caught it while testing a new telescope. It is roughly ten thousand times fainter than its companion, so separating the two takes a good telescope and steady air.
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Illustration generated from temperature, not a photograph
1.0 ☉
mass (the Sun = 1)
25,000 K
surface · blue-white star
0 R☉
radius (the Sun = 1)
9 ly
from Earth
8.4
apparent magnitude
Binoculars needed50 mm binoculars · apparent magnitude 8.4
Its light has been travelling 9 years to reach us, so you see Sirius B as it was 9 years ago.
It lives in
Milky Way
Barred spiral galaxy.
Other notable stars in the Milky Way
Eta CarinaeLuminous blue variableAlnilamBlue supergiantVY Canis MajorisRed hypergiantAlnitakHot blue supergiantDenebBlue-white supergiantMintakaHot blue giant multiple star
Worlds in the same direction on the sky→