Star profile
Alphecca
Alpha Coronae Borealis · Corona Borealis
Variable starWhat is Alphecca
Alphecca, also called Gemma, is the jewel set into the Northern Crown, that small semicircular diadem painted into the northern sky by the Greeks and Romans. It shines with white A-type light, faintly variable because an unseen companion eclipses it briefly every seventeen days or so. At only 75 light-years away, its present glow set out around 1951, when the early jet age was just beginning to compress the world.
Where it is and when to see it
Alphecca lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is May: the Sun sits at the opposite point of the sky and the star culminates around midnight. How high it climbs above the horizon depends on the latitude you watch from.
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The signature wall
Stelvia's sky works like a signature wall: anyone can leave their name and a message on a real star, and that signature goes up on the map for everyone to read. Signing is free.
A signature without a lock can be replaced by someone else's. The lock makes the signature permanent and lets you choose a symbolic name for the star, always shown next to the star's catalogue identifier. How the lock works
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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 Alphecca
- Constellation
- Corona Borealis
- Apparent magnitude
- 2.22
- Distance
- 75.1 light years
- Coordinates (J2000)
- RA 233.672° · Dec 26.715°
- Catalogue
- HIP 76267 · HD 139006
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Corona Borealis
Corona Borealis has 26 stars in Stelvia's catalogue. Here are a few of them.
- NusakanBeta Coronae Borealis3.66
- Gamma Coronae Borealis3.81
- Theta Coronae Borealis4.14
- Epsilon Coronae Borealis4.14
- Delta Coronae Borealis4.59
- Zeta 1 Coronae Borealis4.64
- Tau Coronae Borealis4.73
- Kappa Coronae Borealis4.79