Yellow-white subgiant · Hercules
ζ Herculis
Also known as: ζ Her, HIP 81693
mag 2.835 light-years
About
ζ Herculis is a yellow-white subgiant of magnitude 2.8 in Hercules, about 35 light-years away.
How to find it
- ζ Herculis is in the constellation Hercules.
- Best evenings: around mid-July it is highest at about 9 pm (10 pm in summer time); a month earlier, two hours later.
- Where on Earth: it is seen well, at least 10° up, from north of 48° S.
- Star patterns: Keystone.
When it rises and sets tonight, how high it climbs and how much the Moon gets in the way are worked out in your browser for your place.
What you will see
- EyesEasy, even from town.
- Binoculars (10×50)A sharp point; binoculars bring out its colour and the fainter stars around it.
- Telescope (6–8 inch)Still a point of light at any magnification — stars are too far away to show a disc. Low in the sky, bright stars twinkle and flash colours.
Stars look the same in any instrument: brighter and sharper, but never bigger.
Facts
| Designation | ζ Herculis (ζ Her) |
|---|---|
| Hipparcos number | HIP 81693 |
| Type | Yellow-white subgiant |
| Spectral type | F9IV |
| Colour | YellowB−V colour index 0.65 |
| Magnitude | 2.8The smaller the number, the brighter. |
| Distance | 35 light-yearsThe light you see left it around 1991. |
| Proper motion | 0.58″ per year across the sky |
| Constellation | Hercules |
| Right ascension (J2000) | 16h 41m 17.2s |
| Declination (J2000) | +31° 36′ 10″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →