24 Aquarii
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 21h 39m 31.53468s |
| Declination | −00° 03′ 04.1095″ |
| Apparent magnitude (V) | 6.66 (7.08 + 15.11 + 7.90) |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | F5.5V + M5V + F8V |
| U−B color index | +0.04 +0.005 (Aa) +1.13 (Ab) +0.15 (B) |
| B−V color index | +0.514 +0.459 (Aa) +1.701 (Ab) +0.642 (B) |
| Astrometry | |
| Radial velocity (Rv) | −15.86±0.06 km/s |
| Proper motion (μ) | RA: +215.367 mas/yr Dec.: +17.077 mas/yr |
| Parallax (π) | 22.63±0.25 mas |
| Distance | 144 ± 2 ly (44.2 ± 0.5 pc) |
| Absolute magnitude (MV) | 3.45 |
| Orbit | |
| Primary | 24 Aqr A |
| Name | 24 Aqr B |
| Period (P) | 48.98±0.07 yr |
| Semi-major axis (a) | 0.4250±0.0005″ |
| Eccentricity (e) | 0.8610±0.0002 |
| Inclination (i) | 55.00±0.04° |
| Longitude of the node (Ω) | 140.26±0.05° |
| Periastron epoch (T) | 2020.799±0.003 |
| Argument of periastron (ω) (secondary) | 293.95±0.07° |
| Orbit | |
| Primary | 24 Aqr Aa |
| Name | 24 Aqr Ab |
| Period (P) | 5.883933(15) days |
| Semi-major axis (a) | 0.0706±0.0019 AU |
| Eccentricity (e) | 0.071±0.006 |
| Inclination (i) | 55.8±2.9° |
| Periastron epoch (T) | 46,988.58±0.08 MJD |
| Argument of periastron (ω) (secondary) | 286±5° |
| Semi-amplitude (K1) (primary) | 14.60±0.09 km/s |
| Details | |
| 24 Aqr Aa | |
| Mass | 1.12±0.06 M☉ |
| Radius | 1.23±0.04 R☉ |
| Luminosity | 2.4±0.1 L☉ |
| Surface gravity (log g) | 4.40±0.06 cgs |
| Temperature | 6,483±80 K |
| Metallicity [Fe/H] | –0.09 dex |
| Age | 3.612 Gyr |
| 24 Aqr Ab | |
| Mass | 0.24±0.05 M☉ |
| Radius | 0.28±0.04 R☉ |
| Surface gravity (log g) | 4.80±0.06 cgs |
| Age | 3.612 Gyr |
| 24 Aqr B | |
| Mass | 1.06±0.05 M☉ |
| Radius | 1.02±0.04 R☉ |
| Luminosity | 1.33±0.05 L☉ |
| Surface gravity (log g) | 4.47±0.06 cgs |
| Temperature | 6,150±80 K |
| Age | 3.612 Gyr |
| Other designations | |
| 24 Aqr, BD−00°4245, HD 206058, HIP 106942, SAO 145566, WDS J21395-0003, LTT 8626 | |
| Database references | |
| SIMBAD | data |
24 Aquarii is a triple star system in the equatorial constellation of Aquarius. 24 Aquarii is the Flamsteed designation. The apparent magnitude of this system is 6.66, which, according to the Bortle Dark-Sky Scale, means it is a faint star that is just visible to the naked eye from dark, rural skies. Based on a dynamical parallax measurement, the system is located at a distance of 144 light-years (44 parsecs). The system is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.
The components A and B make up a visual binary wiith an orbital period of 48.98 years and a high eccentricity of 0.8610. Both are main sequence stars with spectral types of F5.5V and F8V, respectively. Component A is itself a single-lined spectroscopic binary with a period of 5.8839 days and an eccentricity of 0.071±0.006, being orbited by a faint red dwarf with a spectral type of M5V.