48 Cassiopeiae: Difference between revisions
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The primary component, '''48 Cassiopeiae A''', is a white [[stellar classification|A-type]] [[main sequence]] star with an [[apparent magnitude]] of +4.630. It has an [[astrometric binary|astrometric]] companion, '''48 Cassiopeiae B''', which is a [[stellar classification|F-type]] [[main sequence|main sequence dwarf]] with an apparent magnitude of +6.681. These two stars orbit around their common centre of mass once every 60.5 years. Component B has a [[semi-major axis]] of 0.62 [[arcsecond]]s, or 22 [[Astronomical Unit|AU]]. The orbit has also been determined spectroscopically, although the accuracy is low.<ref name=mason/> |
The primary component, '''48 Cassiopeiae A''', is a white [[stellar classification|A-type]] [[main sequence]] star with an [[apparent magnitude]] of +4.630. It has an [[astrometric binary|astrometric]] companion, '''48 Cassiopeiae B''', which is a [[stellar classification|F-type]] [[main sequence|main sequence dwarf]] with an apparent magnitude of +6.681. These two stars orbit around their common centre of mass once every 60.5 years. Component B has a [[semi-major axis]] of 0.62 [[arcsecond]]s, or 22 [[Astronomical Unit|AU]]. The orbit has also been determined spectroscopically, although the accuracy is low.<ref name=mason/> |
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A third |
A third star, '''48 Cassiopeiae C''', is a fourteenth magnitude star located 24 [[arcsecond]]s, or at least 850 AU, away. |
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48 Cassiopeiae also has the [[Bayer designation]] A Cassiopeiae, the only star with a Latin letter designation in the constellation.<ref name=cross/> |
48 Cassiopeiae also has the [[Bayer designation]] A Cassiopeiae, the only star with a Latin letter designation in the constellation.<ref name=cross/> |
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Revision as of 20:56, 22 June 2018
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 02h 01m 57.450s[1] |
| Declination | +70° 54′ 25.29″[1] |
| Apparent magnitude (V) | 4.54[2] (+4.630/+6.681)[3] |
| Characteristics | |
| Spectral type | A5V[4] (A2V + F2V)[5] |
| U−B color index | +0.06[2] |
| B−V color index | +0.16[2] |
| Astrometry | |
| Radial velocity (Rv) | −12.4[6] km/s |
| Proper motion (μ) | RA: −55.69 ± 0.41[1] mas/yr Dec.: −8.71 ± 0.46[1] mas/yr |
| Parallax (π) | 28.36 ± 0.44 mas[1] |
| Distance | 115 ± 2 ly (35.3 ± 0.5 pc) |
| Absolute magnitude (MV) | +1.72 |
| Orbit[7] | |
| Companion | 48 Cassiopeiae B |
| Period (P) | 60.55 yr |
| Semi-major axis (a) | 0.628″ |
| Eccentricity (e) | 0.386 |
| Inclination (i) | 19.4° |
| Longitude of the node (Ω) | 188.4° |
| Periastron epoch (T) | 1965.8 |
| Details | |
| 48 Cas | |
| Surface gravity (log g) | 3.7[6] cgs |
| Temperature | 7,700[6] K |
| Metallicity [Fe/H] | −0.4[6] dex |
| Rotational velocity (v sin i) | 60.0[6] km/s |
| A | |
| Mass | 1.92[7] M☉ |
| Luminosity | 16.7[7] L☉ |
| B | |
| Mass | 1.19[7] M☉ |
| Luminosity | 2.29 L☉ |
| Other designations | |
| Database references | |
| SIMBAD | 48 Cas |
| A | |
| B | |
48 Cassiopeiae is a star system in the constellation Cassiopeia. It is approximately 115 light years from Earth.[1]
The primary component, 48 Cassiopeiae A, is a white A-type main sequence star with an apparent magnitude of +4.630. It has an astrometric companion, 48 Cassiopeiae B, which is a F-type main sequence dwarf with an apparent magnitude of +6.681. These two stars orbit around their common centre of mass once every 60.5 years. Component B has a semi-major axis of 0.62 arcseconds, or 22 AU. The orbit has also been determined spectroscopically, although the accuracy is low.[7]
A third star, 48 Cassiopeiae C, is a fourteenth magnitude star located 24 arcseconds, or at least 850 AU, away.
48 Cassiopeiae also has the Bayer designation A Cassiopeiae, the only star with a Latin letter designation in the constellation.[8]
References
- ^ a b c d e f van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.Vizier catalog entry
- ^ a b c Hoffleit, Dorrit; Jaschek, Carlos (1991). "The Bright star catalogue". New Haven. Bibcode:1991bsc..book.....H.
- ^ Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
- ^ Abt, Helmut A; Morrell, Nidia I (1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". The Astrophysical Journal Supplement Series. 99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182.
- ^ Edwards, T. W (1976). "MK classification for visual binary components". The Astronomical Journal. 81: 245. Bibcode:1976AJ.....81..245E. doi:10.1086/111879.
- ^ a b c d e Gebran, M; Farah, W; Paletou, F; Monier, R; Watson, V (2016). "A new method for the inversion of atmospheric parameters of A/Am stars". Astronomy & Astrophysics. 589: A83. arXiv:1603.01146. Bibcode:2016A&A...589A..83G. doi:10.1051/0004-6361/201528052.
- ^ a b c d e Mason, Brian D; Douglass, Geoffrey G; Hartkopf, William I (1999). "Binary Star Orbits from Speckle Interferometry. I. Improved Orbital Elements of 22 Visual Systems". The Astronomical Journal. 117 (2): 1023. Bibcode:1999AJ....117.1023M. doi:10.1086/300748.
- ^ Kostjuk, N. D. (2004). "VizieR Online Data Catalog: HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index (Kostjuk, 2002)". VizieR On-line Data Catalog: IV/27A. Originally published in: Institute of Astronomy of Russian Academy of Sciences (2002). 4027. Bibcode:2004yCat.4027....0K.
