Blue-white giant · Aquila
θ Aquilae
Also known as: θ Aql, HIP 99473
mag 3.2290 light-years
About
θ Aquilae is a blue-white giant of magnitude 3.2 in Aquila, about 290 light-years away.
How to find it
- θ Aquilae is in the constellation Aquila.
- Best evenings: around early 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 south of 79° 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
- EyesVisible from the suburbs on a clear night, but lost in bright city skies.
- 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 Aquilae (θ Aql) |
|---|---|
| Hipparcos number | HIP 99473 |
| Type | Blue-white giant |
| Spectral type | B9.5III |
| Colour | WhiteB−V colour index −0.07 |
| Magnitude | 3.2The smaller the number, the brighter. |
| Distance | 290 light-yearsThe light you see left it around 1740. |
| Proper motion | 0.036″ per year across the sky |
| Constellation | Aquila |
| Right ascension (J2000) | 20h 11m 18.3s |
| Declination (J2000) | −00° 49′ 17″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →