| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Phoenix |
| Right ascension | 01h 32m 32.93s[2] |
| Declination | −49° 31′ 41.29″[2] |
| Apparent magnitude (V) | 7.56 – 8.25[3] |
| Characteristics | |
| Evolutionary stage | G0V + G0V[3] |
| Variable type | W UMa[3] |
| Astrometry | |
| Radial velocity (Rv) | 21.2[4] km/s |
| Proper motion (μ) | RA: +151.48[2]mas/yr Dec.: -53.94[2]mas/yr |
| Parallax (π) | 19.4490±0.0260 mas[2] |
| Distance | 167.7 ± 0.2 ly (51.42 ± 0.07 pc) |
| Absolute magnitude (MV) | 4.104[5] |
| Details | |
| Age | 3.20 ± 1.62[6] Gyr |
| Primary | |
| Mass | 1.38 ± 0.06[7] M☉ |
| Radius | 1.29 ± 0.03[7] R☉ |
| Luminosity | 1.74+0.30 −0.26[7] L☉ |
| Temperature | 6,083[8] K |
| Secondary | |
| Mass | 0.63 ± 0.02[7] M☉ |
| Radius | 0.81 ± 0.02[7] R☉ |
| Luminosity | 0.83+0.15 −0.12[7] L☉ |
| Temperature | 6,310[8] K |
| Other designations | |
| AE Phe,CD−50°410,HD 9528,HIP 7183,SAO 215545[9] | |
| Database references | |
| SIMBAD | data |
AE Phoenicis is avariable star in theconstellation ofPhoenix. Aneclipsing binary, itsapparent magnitude has a maximum of 7.56, dimming to 8.25 during primary eclipse and 8.19 during secondary eclipse.[3] Fromparallax measurements by theGaia spacecraft, the system is located at a distance of 168light-years (51.4parsecs) from Earth.[2]
AE Phoenicis is acontact binary ofW Ursae Majoris type, composed of two stars so close that their surfaces touch each other. They are separated by 2.70solar radii[6] and orbit each other with aperiod of 0.3624 days.[8] They are both classified asG-type main-sequence stars ofspectral type G0V.[3] Witheffective temperatures of 6,083 and 6,310 K, the system is classified as a W Ursae Majoris variable of subtype W, where the secondary star is hotter than the primary; for this reason, the primary eclipses are caused by the occultation of the secondary star.[8] The orbit is circular[10] and isinclined by 86.5° in relation to the plane of the sky.[8]
The combination of photometric and spectroscopic data have allowed the direct determination of the parameters of the stars. The primary component has a mass of 1.38 times thesolar mass and a radius of 1.29 times the solar radius, while the secondary has 0.63 times the solar mass and 0.81 times the solar radius.[7] In visible light, the primary star contributes 66.5% of the system's luminosity, while the secondary contributes the rest (33.5%).[8] Thelight curve shows asymmetries and variations that indicatestarspots on the surface of the stars. The reconstruction of the surface of the system byDoppler imaging revealed significant spot coverage in the entire surface of both stars, and the spots seem to evolve in a timescale of days.[4]
Since the stars are in contact, there is considerablemass transfer from the secondary to the primary. It is estimated that the secondary star was initially the more massive star, with 1.69 times the solar mass, while the primary had an initial mass of 1.02 times the solar mass.[6] Observations show the orbital period of the system to be increasing at a rate of 6.17×10−8 days per year, which is direct evidence of this mass transfer.[8] The system was born as adetached binary with an estimated separation of 12.39 solar radii and period of 3.07 days, which by angular momentum loss evolved to the current contact configuration.[6] In the future the two stars will probably merge into a single, fast-rotating star.[11]
Gaia Data Release 2 catalogued a 16.0-magnitude star (G band) with very similar parallax andproper motions to AE Phoenicis. It is separated from AE Phoenicis by 6.0arcseconds and has a temperature of 4,640 K.[12]
