HD 191984
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| A | |
| Right ascension | 20h 12m 35.12414s |
| Declination | +00° 52′ 01.3827″ |
| Apparent magnitude (V) | 6.246 |
| B | |
| Right ascension | 20h 12m 35.04446s |
| Declination | +00° 51′ 58.9646″ |
| Apparent magnitude (V) | 6.246 |
| Characteristics | |
| Spectral type | B9p CR(EU SR) + A0 |
| U−B color index | −0.033 |
| B−V color index | +0.090 |
| Astrometry | |
| A | |
| Radial velocity (Rv) | −19.0 km/s |
| Proper motion (μ) | RA: +1.577 mas/yr Dec.: −21.256 mas/yr |
| Parallax (π) | 6.4490±0.0534 mas |
| Distance | 506 ± 4 ly (155 ± 1 pc) |
| B | |
| Radial velocity (Rv) | −21.0 km/s |
| Proper motion (μ) | RA: +4.733 mas/yr Dec.: −17.988 mas/yr |
| Parallax (π) | 6.5263 ± 0.0318 mas |
| Distance | 500 ± 2 ly (153.2 ± 0.7 pc) |
| Details | |
| A | |
| Mass | 2.6 M☉ |
| Radius | 2.5 R☉ |
| Luminosity | 60 L☉ |
| Surface gravity (log g) | 3.96 cgs |
| Temperature | 10,497 K |
| Metallicity [Fe/H] | −1.00 dex |
| Rotational velocity (v sin i) | 150 km/s |
| Age | 262 Myr |
| B | |
| Mass | 2.2 M☉ |
| Radius | 2.3 R☉ |
| Luminosity | 31 L☉ |
| Surface gravity (log g) | 3.87 cgs |
| Temperature | 8,801 K |
| Metallicity [Fe/H] | −1.42 dex |
| Age | 574 Myr |
| Other designations | |
| BD+00°4444, HD 191984, HIP 99585, HR 7717. | |
| Database references | |
| SIMBAD | data |
| A | |
| B | |
HD 191984 is a double star in the equatorial constellation of Aquila. As of 2011, the components have an angular separation of 2.52″ along a position angle of 205.7°.