Star profile
4 Herculis
Variable starWhat is 4 Herculis
4 Herculis —also catalogued as V839 Herculis— is a Be star: a hot B-type star wrapped in a disk of gas that the star itself ejects into space through its dizzying rotation. Measurements reveal a 12,500 K surface spinning at more than 300 km/s, and an invisible companion orbiting every 46 days. When the disk forms, the spectrum shows those quasi-emission «shoulders» that betray a star in mid-exhalation.
Where it is and when to see it
4 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 April: 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 4 Herculis
- Constellation
- Hercules
- Apparent magnitude
- 5.73
- Distance
- 536.5 light years
- Coordinates (J2000)
- RA 238.877° · Dec 42.566°
- Catalogue
- HIP 77986 · HD 142926
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
- 16 Herculis5.72
- HIP 858885.72
- HIP 886365.72
- 50 Herculis5.73
- 84 Herculis5.73