White hypergiant · Delphinus
γ¹ Delphini
Also known as: γ¹ Del, HIP 102531
mag 5.2120 light-years
About
γ¹ Delphini is a white hypergiant of magnitude 5.2 in Delphinus, about 120 light-years away.
How to find it
- γ¹ Delphini is in the constellation Delphinus.
- Best evenings: around mid-September 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 64° S.
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
- EyesNeeds a dark sky away from city lights.
- 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 | γ¹ Delphini (γ¹ Del) |
|---|---|
| Hipparcos number | HIP 102531 |
| Type | White hypergiant |
| Spectral type | A2Ia+ |
| Colour | YellowB−V colour index 0.49 |
| Magnitude | 5.2The smaller the number, the brighter. |
| Distance | 120 light-yearsThe light you see left it around 1900. |
| Proper motion | 0.20″ per year across the sky |
| Constellation | Delphinus |
| Right ascension (J2000) | 20h 46m 38.9s |
| Declination (J2000) | +16° 07′ 27″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →