Orange giant · Octans
θ Octantis
Also known as: θ Oct, HIP 122
mag 4.8220 light-years
About
θ Octantis is an orange giant of magnitude 4.8 in Octans, about 220 light-years away.
How to find it
- θ Octantis is in the constellation Octans.
- Best evenings: around early November 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 south of 3° N.
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 | θ Octantis (θ Oct) |
|---|---|
| Hipparcos number | HIP 122 |
| Type | Orange giant |
| Spectral type | K2III |
| Colour | OrangeB−V colour index 1.25 |
| Magnitude | 4.8The smaller the number, the brighter. |
| Distance | 220 light-yearsThe light you see left it around 1810. |
| Proper motion | 0.19″ per year across the sky |
| Constellation | Octans |
| Right ascension (J2000) | 00h 01m 35.8s |
| Declination (J2000) | −77° 03′ 57″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →