Star profile
21 Monocerotis
Variable starWhat is 21 Monocerotis
21 Monocerotis, also known as V571 Monocerotis, is a Delta Scuti variable about 284 light-years away —an A8 star that pulses on periods of only a few hours. Its oscillations are so fast and so subtle that only precision photometry catches them, yet they reshape the entire surface every cycle. It is receding from the Solar System at 30 km/s, faintly throbbing on the winter tapestry of the Unicorn.
Where it is and when to see it
21 Monocerotis lies in the southern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is January: 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 21 Monocerotis
- Constellation
- Monoceros
- Apparent magnitude
- 5.44
- Distance
- 284.4 light years
- Coordinates (J2000)
- RA 107.848° · Dec -0.302°
- Catalogue
- HIP 34724 · HD 55057
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Monoceros
Monoceros has 71 stars in Stelvia's catalogue. Here are a few of them.
- Beta Monocerotis3.76
- Alpha Monocerotis3.94
- Gamma Monocerotis3.99
- HIP 289495.37
- HIP 311215.43
- HIP 331845.44
- HIP 379015.49
- HIP 315835.52