HR 6628, a blue-white bright giant star in Scorpius
HR 6628 is a blue-white bright giant star in the constellation Scorpius. At 557 light years away, it shines at an apparent visual magnitude of 4.80.
HR 6628 (HIP 87220)
HR 6628 is a blue-white bright giant star in the constellation Scorpius. At 557 light years away, it shines at an apparent visual magnitude of 4.80. It is moving through the Galaxy at a speed of 16.0 km/s relative to the Sun.
Sky position: RA 17h 49.2m, Dec -31° 42.2'
Common designations: HR 6628, HD 161840, HIP 87220, Gaia DR3 4055612002737545216
HR 6628 has the spectral type B8Ib/II. 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 II marks it as a bright giant, more luminous than ordinary giants.
How to find HR 6628 in the sky
HR 6628 lies in Scorpius. With a declination of -31° 42.2', it is visible from the entire Southern Hemisphere and from the Northern Hemisphere up to about latitude 58° N. Observers poleward of latitude 58° S see it as circumpolar: it never sets. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around July, which makes the weeks around that month the best time to observe it.
Tabulated data for HR 6628
Astrometry and spectroscopy
| Right Ascension (J2000) | 267.29365502° (17h 49.2m) |
| Declination (J2000) | -31.70320629° (-31° 42.2') |
| Galactic Longitude | 358.02894775° |
| Galactic Latitude | -2.08838551° |
| Proper motion RA | 5.51 mas/yr |
| Proper motion Dec | -9.47 mas/yr |
| Parallax | 5.85 ± 0.13 mas |
| Spectral Type | B8Ib/II |
| Radial Velocity | -13.30 km/s |
Photometry
| Band | Magnitude | Abs. Mag. |
|---|---|---|
| B | 4.75 | -1.41 |
| V | 4.80 | -1.37 |
| J | 4.48 | -1.68 |
| H | 4.79 | -1.38 |
| K | 4.75 | -1.41 |
Colour index B-V: -0.04
Derivations
- Heliocentric distance: 170.86 pc (557 light years) (2.1% margin of error)
- Absolute visual magnitude: -1.37
- Transverse velocity: 8.9 km/s
- Space velocity relative to the Sun: 16.0 km/s
- Galactic position (X, Y, Z): 170.6 pc, -5.9 pc, -6.2 pc
- Galactic velocity (U, V, W): -13.7 km/s, -3.8 km/s, -7.3 km/s
Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.