Blue star · Orion
θ¹ Orionis
Also known as: θ¹ Ori, HIP 26220
mag 5.0
About
θ¹ Orionis is a blue star of magnitude 5.0 in Orion.
How to find it
- θ¹ Orionis is in the constellation Orion.
- Best evenings: around late January 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 75° N.
- Star patterns: Orion’s Belt and Sword.
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 | θ¹ Orionis (θ¹ Ori) |
|---|---|
| Hipparcos number | HIP 26220 |
| Type | Blue star |
| Spectral type | O7 |
| Magnitude | 5.0The smaller the number, the brighter. |
| Proper motion | 0.001″ per year across the sky |
| Constellation | Orion |
| Right ascension (J2000) | 05h 35m 15.8s |
| Declination (J2000) | −05° 23′ 14″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →