KX Andromedae
Appearance
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Andromeda |
Right ascension | 23h 07m 06.2120s[1] |
Declination | +50° 11′ 32.4891″[1] |
Apparent magnitude (V) | 6.88 – 7.28 variable[2] |
Characteristics | |
Spectral type | B3pe+K1III[3] |
Apparent magnitude (U) | 6.79[4] |
Apparent magnitude (B) | 7.25[4] |
Apparent magnitude (V) | 6.92[4] |
Apparent magnitude (G) | 6.8227[1] |
Apparent magnitude (J) | 5.845[5] |
Apparent magnitude (H) | 5.33[4] |
Apparent magnitude (K) | 5.19[4] |
Variable type | Be star |
Astrometry | |
Radial velocity (Rv) | −7.8±0.9[6] km/s |
Proper motion (μ) | RA: 1.697±0.057 [1] mas/yr Dec.: −0.788±0.048[1] mas/yr |
Parallax (π) | 1.2444 ± 0.0328 mas[1] |
Distance | 2,620 ± 70 ly (800 ± 20 pc) |
Orbit[7] | |
Period (P) | 38.919 days |
Eccentricity (e) | 0±0.03 |
Inclination (i) | 50±5° |
Periastron epoch (T) | HJD 2423220.25±0.09 |
Semi-amplitude (K2) (secondary) | 86.2±0.8 km/s |
Details | |
Primary | |
Mass | 9.0±0.1[8] M☉ |
Age | 22.4±3.1[8] Myr |
Secondary | |
Radius | 19±4[7] R☉ |
Surface gravity (log g) | 2.0±0.5[7] cgs |
Temperature | 5000±400[7] K |
Rotational velocity (v sin i) | 25±5[7] km/s |
Other designations | |
Database references | |
SIMBAD | data |
KX Andromedae (often abbreviated to KX And) is a spectroscopic binary star in the constellation Andromeda. Its apparent visual magnitude varies between 6.88 and 7.28.[2]
The primary component of the KX Andromedae system is a Be star with a spectral classification B3pe as in 2017,[2] although on historical record it has varied from B1 to B7.[9]
The secondary star is difficult to detect in the spectrum, but has been given a K1III spectral type. It is likely to be an asymptotic giant branch star that fills its Roche lobe.[7]
The system is only about 25 million years old. The pair complete a circular orbit every 38.919 days at an inclination of 50°.[7]
References
- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c KX And, database entry, Combined General Catalog of Variable Stars (GCVS5.1, 2017 Ed.), N. N. Samus, O. V. Durlevich, et al., CDS ID II/250 Accessed on line 2018-10-17.
- ^ a b c d e Database entry, Catalogue of Stellar Photometry in Johnson's 11-color system (2002 Ed.), J. R. Ducati, CDS ID II/237 Accessed on line 2018-11-10.
- ^ Cutri, R. M.; Skrutskie, M. F.; Van Dyk, S.; et al. (June 2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues. 55 (2246): II/246. Bibcode:2003yCat.2246....0C.
- ^ Pourbaix, D.; et al. (September 2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy and Astrophysics, 424 (2): 727–732, arXiv:astro-ph/0406573, Bibcode:2004A&A...424..727P, doi:10.1051/0004-6361:20041213, S2CID 119387088.
- ^ a b c d e f g Tarasov, A. E.; Berdyugina, S. V.; Berdyugin, A. V. (May 1998), "The massive interacting binary KX And: The orbit and physical parameters of the secondary component", Astronomy Letters, 24 (3): 316–320, Bibcode:1998AstL...24..316T
- ^ a b Tezlaff, N.; Neuhäuser, R.; Hohle, N. N. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873
{{citation}}
: CS1 maint: unflagged free DOI (link) - ^ Properties and nature of Be stars 31. The binary nature, light variability, physical elements, and emission-line changes of HD 81357, 2019, arXiv:1908.02719