Blue-white main-sequence star · Circinus
θ Circini
Also known as: θ Cir, HIP 73129
mag 5.11,500 light-years
About
θ Circini is a blue-white main-sequence star of magnitude 5.1 in Circinus, about 1,500 light-years away.
How to find it
- θ Circini is in the constellation Circinus.
- Best evenings: around late June 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 17° 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 Circini (θ Cir) |
|---|---|
| Hipparcos number | HIP 73129 |
| Type | Blue-white main-sequence star |
| Spectral type | B4Vnp |
| Colour | WhiteB−V colour index −0.02 |
| Magnitude | 5.1The smaller the number, the brighter. |
| Distance | 1,500 light-yearsThe light you see left it around AD 500. Distances this large are uncertain by 10% or more. |
| Proper motion | 0.017″ per year across the sky |
| Constellation | Circinus |
| Right ascension (J2000) | 14h 56m 44.0s |
| Declination (J2000) | −62° 46′ 52″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →