Alpha Sculptoris, a blue-white giant star in Sculptor
Alpha Sculptoris is a blue-white giant star in the constellation Sculptor. At 706 light years away, it shines at an apparent visual magnitude of 4.27.
Alpha Sculptoris (HIP 4577)
Alpha Sculptoris is a blue-white giant star in the constellation Sculptor. At 706 light years away, it shines at an apparent visual magnitude of 4.27. It is moving through the Galaxy at a speed of 23.2 km/s relative to the Sun.
Sky position: RA 0h 58.6m, Dec -29° 21.4'
Common designations: Alpha Sculptoris, HR 280, HD 5737, HIP 4577, Gaia DR3 5032256161014732416
Alpha Sculptoris has the spectral type B7IIIp. B-type stars are hot (about 10,000 to 30,000 K), luminous and blue-white. They are massive, short-lived stars, typically only tens of millions of years old, and are common in young clusters and OB associations. Its luminosity class III marks it as a giant: an evolved star that has left the main sequence and swollen to many times its original size.
How to find Alpha Sculptoris in the sky
Alpha Sculptoris lies in Sculptor. With a declination of -29° 21.4', it is visible from the entire Southern Hemisphere and from the Northern Hemisphere up to about latitude 61° N. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around October, which makes the weeks around that month the best time to observe it.
Tabulated data for Alpha Sculptoris
Astrometry and spectroscopy
| Right Ascension (J2000) | 14.65149694° (0h 58.6m) |
| Declination (J2000) | -29.35745339° (-29° 21.4') |
| Galactic Longitude | 268.04670716° |
| Galactic Latitude | -87.26852942° |
| Proper motion RA | 19.97 mas/yr |
| Proper motion Dec | 5.07 mas/yr |
| Parallax | 4.62 ± 0.19 mas |
| Spectral Type | B7IIIp |
| Radial Velocity | 9.60 km/s |
Photometry
| Band | Magnitude | Abs. Mag. |
|---|---|---|
| U | 3.52 | -3.16 |
| B | 4.09 | -2.59 |
| V | 4.27 | -2.41 |
| R | 4.30 | -2.38 |
| I | 4.43 | -2.25 |
| J | 4.63 | -2.05 |
| H | 4.81 | -1.87 |
| K | 4.67 | -2.01 |
Colour index B-V: -0.18
Derivations
- Heliocentric distance: 216.34 pc (706 light years) (4.1% margin of error)
- Absolute visual magnitude: -2.41
- Transverse velocity: 21.1 km/s
- Space velocity relative to the Sun: 23.2 km/s
- Galactic position (X, Y, Z): -0.4 pc, -10.3 pc, -216.1 pc
- Galactic velocity (U, V, W): -19.9 km/s, -7.5 km/s, -9.2 km/s
Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.