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Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Vulpecula |
Right ascension | 19h 51m 04.1083s[1] |
Declination | +22° 36′ 36.173″[1] |
Apparent magnitude (V) | 4.928±0.015[2] (4.78 - 4.97)[3] |
Characteristics | |
Spectral type | B2.5V[4] |
Apparent magnitude (U) | 4.104±0.020[2] |
Apparent magnitude (B) | 4.759±0.017[2] |
Variable type | Be star[3] |
Astrometry | |
Radial velocity (Rv) | −24.90[5] km/s |
Proper motion (μ) | RA: 23.404±0.068[1] mas/yr Dec.: −15.797±0.099[1] mas/yr |
Parallax (π) | 5.1710 ± 0.1070 mas[1] |
Distance | 630 ± 10 ly (193 ± 4 pc) |
Absolute magnitude (MV) | −1.52[4] |
Details | |
Mass | 6.8[6] M☉ |
Luminosity | 963[4] L☉ |
Surface gravity (log g) | 3.36[7] cgs |
Temperature | 18,859[7] K |
Metallicity [Fe/H] | −0.01[7] dex |
Rotational velocity (v sin i) | 195[8] km/s |
Other designations | |
Database references | |
SIMBAD | data |
12 Vulpeculae is a star in the northern constellation of Vulpecula, located approximately 630 light years away based on parallax.[1] It has the variable star designation V395 Vul; 12 Vulpeculae is the Flamsteed designation. This object is visible to the naked eye as a faint, blue-white hued star with a baseline apparent visual magnitude of 4.928.[2] It is moving closer to the Earth with a heliocentric radial velocity of -25 km/s.[5]
This is a variable Be star with a stellar classification of B2.5V;[4] its brightness ranges from magnitude 4.78 down to 4.97.[3] As is true with other Be stars, it has a high rate of rotation with a projected rotational velocity of 195 km/s.[8] The star has 6.8[6] times the mass of the Sun and is radiating 963[4] times the Sun's luminosity from its photosphere at an effective temperature of 18,859 K.[7]