Star · B2IV
θ¹ Sgr
θ¹ Sgr is a subgiant star of spectral type B2IV in the constellation Sagittarius, 670.8 light-years from the Sun.
| Other names | HIP 98412 |
|---|---|
| Constellation | Sagittarius |
| Distance | 670.8 light-years (205.7 pc) |
| Apparent magnitude | magnitude 4.37 |
| Absolute magnitude | magnitude −2.20 |
| Spectral type | B2IV |
| Surface temperature | 12,490 K |
| Luminosity | 1,340 L☉ |
| Radius | 7.81 R☉ |
| Mass | 7.1 M☉ (estimated) |
| Right ascension (J2000) | 19h 59m 44.2s |
| Declination (J2000) | −35° 16′ 35″ |
| Space velocity (relative to the Sun) | 25.1 km/s |
In the sky
Visible to the naked eye under a dark sky (apparent magnitude 4.37). Visible from the whole Southern Hemisphere and north to latitude 55° N. South of latitude 55° S it never sets. It stands highest at midnight in July, the best time to observe it.
Through a telescope from Earth
Light's journey
The light you see tonight set out around the year 1355. At the speed of Voyager 1, the fastest craft leaving the Solar System (16.9 km per second), the trip would take 12 million years.
The Sun seen from there
From a planet around θ¹ Sgr, the Sun would look like a star of magnitude 11.40, in the direction where our sky has the constellation Lynx. It would be invisible to the naked eye.
Position, brightness and colour from the HYG / AT-HYG catalogue; temperature, luminosity, radius and mass are approximate values computed from these observations.