Alnilam is the middle star of Orion’s belt, a hot blue-white supergiant so luminous that it shines brightly in our sky despite lying far behind its neighbours.
At a glance
| type | blue-white supergiant (class B) |
|---|---|
| distance from the Sun | 1,980 light-years (606 pc) |
| its light left it | 1,980 years ago |
| luminosity | 1.07 million × the Sun |
| radius | 38.3 × the Sun |
| surface temperature | 30,000 K |
| constellation | Orion (Hunter) |
Read off the piece’s own catalogue, the same values it draws with.
About Alnilam
Alnilam is one of the most luminous stars the eye can see: a hot, massive blue-white supergiant of class B, swollen and shedding a strong wind of gas into space. Its light partly illuminates the clouds of the Orion region around it.
The name comes from Arabic for a string of pearls, the belt itself. Alnilam is the farthest of the three belt stars and still holds its own beside them, a sign of its extraordinary power. It is one of the stars used for celestial navigation. Stars this massive live briefly, and it will probably end as a supernova.
What you see in the piece
The belt is a straight line only from here; in the piece Alnilam lies far behind Mintaka and Alnitak, and flying towards it makes the belt fold up along the line of sight.
Measured or modelled
Alnilam’s exact distance, and so its true luminosity, have varied between studies; the card gives the value the catalogue uses.
Questions
What is the middle star of Orion’s belt?
The middle star of Orion’s belt is Alnilam, a hot blue-white supergiant 1.07 million times as luminous as the Sun.
How far away is Alnilam?
Alnilam is 1,980 light-years (606 pc) from the Sun, the farthest of the three belt stars.