26 Andromedae
26 Andromedae, abbreviated 26 And, is a binary star system in the constellation Andromeda. 26 Andromedae is the Flamsteed designation. It has a combined apparent visual magnitude of 6.10, which is near the lower limit of visibility to the naked eye. The distance to this system can be estimated from its annual parallax shift of 5.35 mas, which yields a distance of about 600 light years. At that distance, the visual magnitude of the stars is diminished from an extinction of 0.04 due to interstellar dust. The system is moving further from the Earth with a heliocentric radial velocity of +3.3 km/s.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| A | |
| Right ascension | 00h 18m 42.16888s |
| Declination | +43° 47′ 28.1082″ |
| Apparent magnitude (V) | 6.11 |
| B | |
| Right ascension | 00h 18m 41.66160s |
| Declination | +43° 47′ 24.9776″ |
| Apparent magnitude (V) | 9.70 |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | B8 V + F3 V |
| B−V color index | −0.074±0.004 |
| Variable type | suspected |
| Astrometry | |
| A | |
| Radial velocity (Rv) | +3.3 km/s |
| Proper motion (μ) | RA: 23.328 mas/yr Dec.: −2.755 mas/yr |
| Parallax (π) | 5.3927 ± 0.0192 mas |
| Distance | 605 ± 2 ly (185.4 ± 0.7 pc) |
| Absolute magnitude (MV) | 0.02 |
| B | |
| Proper motion (μ) | RA: 22.083 mas/yr Dec.: −3.568 mas/yr |
| Parallax (π) | 5.4683 ± 0.0142 mas |
| Distance | 596 ± 2 ly (182.9 ± 0.5 pc) |
| Absolute magnitude (MV) | 4.00 |
| Details | |
| A | |
| Mass | 3.54±0.12 M☉ |
| Radius | 3.76 R☉ |
| Luminosity | 219 L☉ |
| Surface gravity (log g) | 3.82 cgs |
| Temperature | 11,939 K |
| Rotational velocity (v sin i) | 18 km/s |
| Age | 95 Myr |
| B | |
| Mass | 1.0 M☉ |
| Radius | 1.2 R☉ |
| Luminosity | 1.5 L☉ |
| Surface gravity (log g) | 4.32 cgs |
| Temperature | 5,924 K |
| Age | 6.1 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The magnitude 6.11 primary, component A, is a B-type main-sequence star with a stellar classification of B8 V. The star has 3.54 times the mass of the Sun and 3.76 times the Sun's radius. It is around 95 million years old and is spinning with a projected rotational velocity of 18 km/s. 26 And is radiating 219 times the Sun's luminosity from its photosphere at an effective temperature of 11,939 K. It displays an infrared excess that suggests a circumstellar debris disk orbiting at a distance of 169.3 AU from the star with a temperature of 75 K.
The fainter secondary, component B, is a magnitude 9.70 star located 6.2″ from the primary. It is an F-type main-sequence star with a class of F3 V that shows an unexplained long term variability.
One of the components of this system displays a slight photometric variation with a period of 3.16 days. This may be caused by pulsation or an ellipsoidal variation. This system's X-ray emission hasn't been detected yet, with an upper limit of Lx < 29.79 erg/s.