Star profile
Phi Herculis
Hot blue starWhat is Phi Herculis
Phi Herculis is a chemically peculiar star of the mercury-manganese class: its atmosphere holds these heavy metals in concentrations thousands of times richer than the Sun's. To the eye it looks single, but spectrographs uncovered a hidden companion, an A8 star spinning far faster than the primary. It burns blue-white near 10,000 K at 204 light-years, owner of a strange chemistry that still puzzles astrophysicists.
Where it is and when to see it
Phi Herculis 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 Phi Herculis
- Constellation
- Hercules
- Apparent magnitude
- 4.23
- Distance
- 204.0 light years
- Coordinates (J2000)
- RA 242.192° · Dec 44.935°
- Catalogue
- HIP 79101 · HD 145389
A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.
Other stars in Hercules
Hercules has 136 stars in Stelvia's catalogue. Here are a few of them.
- KornephorosBeta Herculis2.78
- RasalgethiAlpha 1 Herculis2.78
- Zeta Herculis2.81
- Rho Herculis4.15
- 110 Herculis4.19
- Sigma Herculis4.20
- 95 Herculis4.26
- 111 Herculis4.34