Star profile
Algol
Beta Persei · Perseus
Variable starWhat is Algol
Algol is Perseus's fabled «demon's head», a name drawn from the Arabic «raʾs al-ġūl». Every 2.87 days its brightness drops in a way the naked eye can register, and for centuries it was thought a cursed star; today we know it as an eclipsing system, where an unseen companion passes periodically in front of the brighter star. Its light travels barely 90 years to reach us — still carrying an echo of those ancient fears.
Where it is and when to see it
Algol lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is November: 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 Algol
- Constellation
- Perseus
- Apparent magnitude
- 2.09
- Distance
- 89.9 light years
- Coordinates (J2000)
- RA 47.042° · Dec 40.956°
- Catalogue
- HIP 14576 · HD 19356
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Perseus
Perseus has 99 stars in Stelvia's catalogue. Here are a few of them.
- MirfakAlpha Persei1.79
- Zeta Persei2.84
- Epsilon Persei2.90
- Gamma Persei2.91
- Delta Persei3.01
- Rho Persei3.32
- MiramEta Persei3.77
- Nu Persei3.77