Mu Persei, a yellow supergiant star in Perseus
Mu Persei is a yellow supergiant star in the constellation Perseus. At 828 light years away, it shines at an apparent visual magnitude of 4.16.
Mu Persei (HIP 19812)
Mu Persei is a yellow supergiant star in the constellation Perseus. At 828 light years away, it shines at an apparent visual magnitude of 4.16. It is moving through the Galaxy at a speed of 34.3 km/s relative to the Sun.
Sky position: RA 4h 14.9m, Dec +48° 24.6'
Common designations: Mu Persei, 51 Persei, HR 1303, HD 26630, Gaia DR3 246265388874592768, HIP 19812
Mu Persei has the spectral type G0Ib. G-type stars are yellow stars of about 5,300 to 6,000 K, the same class as the Sun. Their spectra show strong lines of ionized calcium and many metals. Its luminosity class I marks it as a supergiant, among the most luminous and largest stars known.
How to find Mu Persei in the sky
Mu Persei lies in Perseus. With a declination of +48° 24.6', it is visible from the entire Northern Hemisphere and from the Southern Hemisphere down to about latitude 42° S. Observers poleward of latitude 42° N 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 December, which makes the weeks around that month the best time to observe it.
Tabulated data for Mu Persei
Astrometry and spectroscopy
| Right Ascension (J2000) | 63.72443131° (4h 14.9m) |
| Declination (J2000) | 48.40933065° (+48° 24.6') |
| Galactic Longitude | 153.93927342° |
| Galactic Latitude | -1.82441387° |
| Proper motion RA | 6.54 mas/yr |
| Proper motion Dec | -16.89 mas/yr |
| Parallax | 3.94 ± 0.27 mas |
| Spectral Type | G0Ib |
| Radial Velocity | 26.46 km/s |
Photometry
| Band | Magnitude | Abs. Mag. |
|---|---|---|
| U | 5.75 | -1.27 |
| B | 5.12 | -1.90 |
| V | 4.16 | -2.86 |
| R | 3.38 | -3.64 |
| I | 2.83 | -4.19 |
| J | 2.44 | -4.58 |
| H | 2.16 | -4.86 |
| K | 1.92 | -5.10 |
Colour index B-V: +0.96
Derivations
- Heliocentric distance: 253.84 pc (828 light years) (6.8% margin of error)
- Absolute visual magnitude: -2.86
- Transverse velocity: 21.8 km/s
- Space velocity relative to the Sun: 34.3 km/s
- Galactic position (X, Y, Z): -227.9 pc, 111.5 pc, -8.1 pc
- Galactic velocity (U, V, W): -32.2 km/s, -6.2 km/s, -10.1 km/s
Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.