Star profile
42 Persei
Variable starWhat is 42 Persei
42 Persei is a short-period spectroscopic binary: the primary, a white A3V star twice the Sun's mass and nearly sixty times its luminosity, sweeps around an invisible red dwarf companion in just 1.77 days, distorted by the encounter. That distortion drives a brightness drift between magnitudes 5.05 and 5.18. At 269 light-years, it is a silent waltzer mid-stride across Perseus.
Where it is and when to see it
42 Persei 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 42 Persei
- Constellation
- Perseus
- Apparent magnitude
- 5.14
- Distance
- 268.5 light years
- Coordinates (J2000)
- RA 57.386° · Dec 33.091°
- Catalogue
- HIP 17886 · HD 23848
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
- AlgolBeta Persei2.09
- Zeta Persei2.84
- HIP 152195.04
- 31 Persei5.05
- 21 Persei5.10
- 9 Persei5.16
- 29 Persei5.16