Star profile
Alpha Caelum
What is Alpha Caelum
Alpha Caeli is the brightest light of its tiny constellation, the Chisel —one of the figures that French astronomer Lacaille carved into the southern sky in the eighteenth century to honour the instruments of the workshop. Just 66 light-years away, it is a double system: an F2V primary with a debris disc detected around it, and a small red dwarf companion that flares up in sudden bursts. The pair takes 1110 years to complete one orbit.
Where it is and when to see it
Alpha Caelum lies in the southern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is November, when it culminates around midnight.
- From London it never rises above the horizon.
- From New York it culminates about 7° above the horizon.
- From Sydney it culminates about 82° above the horizon.
It can be seen from anywhere south of 48° N.
It is the brightest of the 7 stars of Caelum in our catalogue, which makes it the best starting point for finding your way around the constellation.
The light you see today left it about 66 years ago.
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A public signature from a real person. The chosen name is a symbolic denomination within Stelvia, with no official standing or IAU recognition: the sky is not for sale and belongs to no one.
Astronomical data for Alpha Caelum
- Constellation
- Caelum
- Apparent magnitude
- 4.44
- Distance
- 65.8 light years
- Coordinates (J2000)
- RA 70.141° · Dec -41.864°
- Catalogue
- HIP 21770 · HD 29875
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Other stars in Caelum
Caelum has 7 stars in Stelvia's catalogue. Here are a few of them.
See all 7 stars in Caelum