BD Phoenicis
Variable star in the constellation of Phoenix
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BD Phoenicis is a variable star in the constellation of Phoenix. From parallax measurements by the Gaia spacecraft, it is located at a distance of 256 light-years (78 parsecs) from Earth.[2] Its absolute magnitude is calculated at 1.5.[1]
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Phoenix |
| Right ascension | 01h 50m 54.44s[2] |
| Declination | −50° 12′ 22.09″[2] |
| Apparent magnitude (V) | 5.90 – 5.94[3] |
| Characteristics | |
| Spectral type | A1Va λ Boo[4] |
| Variable type | δ Scuti[3] |
| Astrometry | |
| Radial velocity (Rv) | 3.0[5] km/s |
| Proper motion (μ) | RA: -47.85[2] mas/yr Dec.: -3.70[2] mas/yr |
| Parallax (π) | 12.7260±0.0447 mas[2] |
| Distance | 256.3 ± 0.9 ly (78.6 ± 0.3 pc) |
| Absolute magnitude (MV) | 1.5 ± 0.1[1] |
| Details | |
| Mass | 2.02 ± 0.04[1] M☉ |
| Luminosity | 20.5 ± 0.34[6] L☉ |
| Surface gravity (log g) | 3.91 ± 0.08[1] cgs |
| Temperature | 7,818 ± 38[6] K |
| Rotational velocity (v sin i) | 120 ± 5 [1] km/s |
| Age | 813+38 −89[1] Myr |
| Other designations | |
| BD Phe, CD−50°514, HD 11413, HIP 8593, HR 541, SAO 232542[7] | |
| Database references | |
| SIMBAD | data |
Description
BD Phoenicis is a Lambda Boötis star, an uncommon type of peculiar stars that have very low abundances of iron-peak elements. In particular, BD Phoenicis has near-solar carbon and oxygen content, but its iron abundance is only 4% of the solar value.[1] BD Phoenicis is also a pulsating variable of Delta Scuti type, varying its apparent magnitude between 5.90 and 5.94.[3] A study of its light curve detected seven pulsation periods that range from 50 to 84 minutes, the strongest one having a period of 57 minutes and an amplitude of 9 milli-magnitudes. Pulsations are common among Lambda Boötis stars and seem to be more common than normal main sequence stars of the same spectral type.[1]
BD Phoenicis is an A-type main-sequence star with a spectral type of A1Va.[4] Stellar evolution models indicate it contains double the solar mass and an age of about 800 million years—having completed 83% of its main sequence lifetime.[1] It is radiating 21 times the Sun's luminosity from its photosphere at an effective temperature of 7800 K.[6] BD Phoenicis has a composite spectra that indicate it is a binary star, but nothing is known about its companion.[8][6]
Observations by the Herschel Space Observatory have detected an infrared excess from BD Phoenicis, indicating that there is a debris disk in the system. By modeling the emission as a black body, it is estimated that the dust has a temperature of 55±2 K and is at a distance of 118±10 au from the star. The existence of debris disks is possibly related to the Lambda Boötis phenomenon.[6]