Star profile
30 Herculis
Variable starWhat is 30 Herculis
30 Herculis is a variable M-type red giant, also catalogued as g Herculis, whose light slowly rises and falls with the pulsations that sweep through its swollen atmosphere. It sits about 354 light-years away in the western reach of Hercules. Early catalogues marked it as one of the first known semiregular variables —a star that breathes in long, slow cycles, almost indifferent to human haste.
Where it is and when to see it
30 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, when it culminates around midnight.
- From London it never sets and culminates about 80° up.
- From New York it culminates about 89° above the horizon.
- From Sydney it culminates about 14° above the horizon.
It can be seen from anywhere north of 48° S.
It ranks no. 33 in brightness among the 136 stars of Hercules in our catalogue. To find it, start from Kornephoros, the brightest: it lies about 20° away (a fist at arm's length covers about 10°).
The light you see today left it about 350 years ago.
It opens in your browser. Free, no account, nothing to install.
Leave your signature on 30 Herculis
Your name and a message go up on the map for everyone to read. Signing is free.
Without a lock, someone else can replace your signature. How the lock works
We'll ask for an email to confirm it's you, no password.
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 30 Herculis
- Constellation
- Hercules
- Apparent magnitude
- 4.83
- Distance
- 354.2 light years
- Coordinates (J2000)
- RA 247.161° · Dec 41.882°
- Catalogue
- HIP 80704 · HD 148783
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
- Upsilon Herculis4.72
- 68 Herculis4.80
- 52 Herculis4.82
- 29 Herculis4.84
- 42 Herculis4.86