AR Cassiopeiae
Coordinates: 23h 30m 0s, +58° 33′ 0″
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cassiopeia[2] |
AB | |
Right ascension | 23h 30m 01.93946s[3] |
Declination | +58° 32′ 56.1120″[3] |
Apparent magnitude (V) | 4.883 (4.912 / 8.814)[4] |
CD | |
Right ascension | 23h 29m 52.2802s[5] |
Declination | +58° 32′ 54.458″[5] |
Apparent magnitude (V) | 7.09[6] |
Characteristics | |
AB | |
Spectral type | B4 V + A6 V[4] |
U−B color index | −0.62[7] |
B−V color index | −0.12[7] |
Variable type | Algol[8] |
CD | |
Spectral type | B9 V[6] |
U−B color index | −0.14[7] |
B−V color index | +0.01[7] |
FG | |
Spectral type | F7 IV + F9 V[9] |
Astrometry | |
Radial velocity (Rv) | -15.9 ± 0.9[10] km/s |
Proper motion (μ) | RA: 17.90[3] mas/yr Dec.: 4.15[3] mas/yr |
Parallax (π) | 5.25 ± 0.52[3] mas |
Distance | 620 ± 60 ly (190 ± 20 pc) |
Aa | |
Absolute magnitude (MV) | −1.87 ± 0.13[4] |
Absolute bolometric magnitude (Mbol) | −3.56 ± 0.13[4] |
Ab | |
Absolute magnitude (MV) | 2.20 ± 0.11[4] |
Absolute bolometric magnitude (Mbol) | 2.18 ± 0.11[4] |
Orbit[4] | |
Primary | Aa |
Companion | Ab |
Period (P) | 6.0663170 d |
Eccentricity (e) | 0.240 |
Inclination (i) | 85.34 ± 0.50° |
Periastron epoch (T) | JD 2436847.9404 ± 0.0055 |
Argument of periastron (ω) (secondary) | 41.82 ± 0.47° |
Details[4] | |
Aa | |
Mass | 5.90 ± 0.20 M☉ |
Radius | 5.05 ± 0.06 R☉ |
Surface gravity (log g) | 3.80 ± 0.02 cgs |
Temperature | 17200 ± 500 K |
Ab | |
Mass | 1.86 ± 0.06 M☉ |
Radius | 1.60 ± 0.03 R☉ |
Surface gravity (log g) | 4.30 ± 0.02 cgs |
Temperature | 8150 ± 200 K |
Other designations | |
Database references | |
SIMBAD | AR Cas AB |
AR Cas CD | |
AR Cas D | |
AR Cas F | |
AR Cas G |
AR Cassiopeiae (AR Cas) is a multiple star system in the constellation of Cassiopeia. It is thought to be a septuple star system. It is one of only two known star systems with a multiplicity of 7, the other being Nu Scorpii, with no physical multiple stars of greater multiplicity yet found as of January 2020.[11][9][12]
Nomenclature[]
AR Cassiopeiae was frequently referred to as IH Cas in some literature.[13] The origin of the designation "IH Cassiopeiae" is from the 17th century catalogue and constellation map by Johannes Hevelius, which was kept in use due to the lack of a Flamsteed designation or Bayer designation for the star.[13] It was the first star in Cassiopeia that Flamsteed's edition of Hevelius catalogued,[14] thus "1 Hev. Cas" or "1 H. Cas" (similar to Gould designations), which becomes IH Cas through corruption.[13]
Properties[]
The primary subsystem, AR Cassiopeiae AB, is a triple. AR Cassiopeiae B is located 0.800″ away from AR Cassiopeiae A.[9] AR Cassiopeiae A itself an Algol-type eclipsing binary[8] with an orbital period of about 6.07 days.[4] Its primary is a B-type main-sequence star, and the secondary, an A-type main-sequence star. The secondary star may be an Am star as well.[4]
Farther out are two other stars, designated AR Cassiopeiae C and D, respectively. They are 76.1″ (or about 1.27′) away from the central system.[9] Their combined spectrum matches that of another B-type main-sequence star.[6] This pair is also designated HD 221237.[6] 67.2″ (1.12′) away from AR Cassiopeiae AB is another pair of stars, F and G, both F-type stars.[9] All four of these stars are known to be common proper motion companions.[9]
References[]
- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
- ^ WikiSky, "HD 221253" (accessed 2010-10-27)
- ^ a b c d e van Leeuwen, F.; et al. (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. S2CID 18759600.
- ^ a b c d e f g h i j Holmgren, D. E.; Hadrava, P.; Harmanec, P.; Eenens, P.; Corral, L. J.; Yang, S.; Ak, H.; Bozić, H. (1999). "Search for forced oscillations in binaries. III. Improved elements and the detection of line-profile variability of the B4V + A6V: system AR Cassiopeiae". Astronomy and Astrophysics. 345: 855. Bibcode:1999A&A...345..855H.
- ^ a b Gaia Collaboration (2016). "Gaia Data Release 1". Astronomy & Astrophysics. 595: A2. arXiv:1609.04172. Bibcode:2016A&A...595A...2G. doi:10.1051/0004-6361/201629512. S2CID 1828208.
- ^ a b c d "HD 221237". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 23 August 2017.
- ^ a b c d Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
- ^ a b c "V* AR Cas". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 23 August 2017.
- ^ a b c d e f Tokovinin, A. A. (1997). "MSC - a catalogue of physical multiple stars". Astronomy and Astrophysics Supplement Series. 124: 75–84. Bibcode:1997A&AS..124...75T. doi:10.1051/aas:1997181.
- ^ Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Washington. Bibcode:1953GCRV..C......0W.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID 14878976.
- ^ Bob Argyle, ed. (2004). Observing and Measuring Visual Double Stars. Patick Moore's Practical Astronomy Series. Springer-Verlag. p. 9. ISBN 1-85233-558-0.
- ^ a b c Somerville, W. B. (1986). "1H. Cas = AR Cas". The Observatory. 106: 40–42. Bibcode:1986Obs...106...40S.
- ^ Flamsteed, J., ed. (1725). "Johannis Hevelii Catalogus Stellarum Fixarum Ad Annum Christi 1660 completum". Historia Coelestis Britannica. 3: 54.CS1 maint: extra text: authors list (link)
- Cassiopeia (constellation)
- Algol variables
- Multiple star systems
- Objects with variable star designations
- Durchmusterung objects
- Henry Draper Catalogue objects
- HR objects
- Hipparcos objects
- B-type subgiants