Iota2 Scorpii
ι2 Scorpii, Latinised as Iota2 Scorpii, is a single star in tail of the zodiac constellation of Scorpius. It has an apparent visual magnitude of +4.82, and is visible to the naked eye. Because of parallax measurement errors, the distance to this star is only approximately known: it lies around 2,500 light years away from the Sun. It has a visual companion, a magnitude 11.0 star at an angular separation of 31.60 arcseconds along a position angle of 36°, as of 2000.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17h 50m 11.11291s |
| Declination | −40° 05′ 25.5629″ |
| Apparent magnitude (V) | +4.82 |
| Characteristics | |
| Spectral type | A2 Ib or A6 Ib |
| U−B color index | +0.19 |
| B−V color index | +0.25 |
| Astrometry | |
| Radial velocity (Rv) | −10.2 km/s |
| Proper motion (μ) | RA: +3.90 mas/yr Dec.: −2.42 mas/yr |
| Parallax (π) | 1.28 ± 0.24 mas |
| Distance | approx. 2,500 ly (approx. 800 pc) |
| Absolute magnitude (MV) | −4.59 |
| Details | |
| Mass | 8.8±0.2 M☉ |
| Luminosity | 5,798 L☉ |
| Temperature | 6,372 K |
| Age | 29.8±4.3 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
In the literature, there are two different stellar classifications for this star: A2 Ib and A6 Ib. In either case it is an A-type supergiant star with an estimated age of 30 million years and a mass 8.8 times that of the Sun. It shines with a luminosity 5,798 times the Sun's from an outer atmosphere that has an effective temperature of 6,372 K. As with other stars of its type, ι2 Scorpii varies slightly in brightness, showing an amplitude of 0.05 in magnitude.