Star profile
Epsilon Herculis
What is Epsilon Herculis
Epsilon Herculis is one of the four corners of the Keystone, the luminous trapezoid that defines the torso of Hercules in the northern summer sky. The faintest of the four, it is a white A0 star at 155 light-years, in fact a spectroscopic binary whose components reveal themselves only through the sway of their spectral lines. Without it, the celestial hero's geometry would collapse.
Where it is and when to see it
Epsilon 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 Epsilon Herculis
- Constellation
- Hercules
- Apparent magnitude
- 3.92
- Distance
- 155.0 light years
- Coordinates (J2000)
- RA 255.072° · Dec 30.926°
- Catalogue
- HIP 83207 · HD 153808
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
- 109 Herculis3.85
- Theta Herculis3.86
- Tau Herculis3.91
- Rho Herculis4.15
- 110 Herculis4.19