| |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 19h21m 37.11363s[2] |
| Declination | −19° 14′ 04.0500″[2] |
| Apparent magnitude (V) | 6.25[3] |
| Characteristics | |
| Spectral type | B5III[4] |
| B−V color index | −0.091±0.004[3] |
| Variable type | SPB[5] |
| Astrometry | |
| Radial velocity (Rv) | −23.3±7.4[6] km/s |
| Proper motion (μ) | RA: +3.135 mas/yr Dec.: −12.136 mas/yr |
| Parallax (π) | 4.7371 ± 0.0556 mas[2] |
| Distance | 689 ± 8 ly (211 ± 2 pc) |
| Absolute magnitude (MV) | −0.63[3] |
| Details[5] | |
| Mass | 4.2±0.3 M☉ |
| Radius | 2.9±0.5 R☉ |
| Luminosity | 316+82 −66 L☉ |
| Surface gravity (log g) | 4.16±0.20 cgs |
| Temperature | 14,700±700 K |
| Rotational velocity (v sin i) | 6±4 km/s |
| Age | 48.9±21.6[7] Myr |
| Other designations | |
173 G. Sagittarii, BD−19°5412, HD 181558, HIP 95159, HR 7339, SAO 162511, WDS 19216-1914[8] | |
| Database references | |
| SIMBAD | data |
V4199 Sagittarii is a variable star in the southern constellationofSagittarius.[8] It is a dim star that is just visible to the naked eye with an apparent visual magnitude that varies between 6.22 and 6.28 over a period of 1.23825 days.[9] The star is located at a distance of approximately 689 light years from the Sun based on parallax, but is drifting closer with a radial velocity of roughly −23 km/s.[6] It has an absolute magnitude of −0.63,[3] on average.
The stellar classification of this star is B5III,[4] matching a B-type giant star. In the Bright Star Catalogue it was listed as a main sequence star of class B5V, although the colors suggest a somewhat more evolved star.[10] The photometric variability of this star was announced by C. Waelkens and F. Rufener in 1984.[11] It is a multi-periodic[10] slowly pulsating B star with a dominant frequency of 0.80780±0.00010 cycles/day.[12] The star has four times the mass of the Sun and three times the Sun's radius. It is radiating ~316 times the luminosity of the Sun from its photosphere at an effective temperature of 14,700 K. A magnetic field has been detected on this star with a strength of −104±32 G.[5]
It has a magnitude 9.96 companion star at an angular separationof90.9″ along a position angle of 310°, as of 2003.[13]
