}}{{Starbox reference
| Simbad = WZ+Cas
}}{{Starbox end}}WZ Cassiopeiae (WZ Cas) is a deep red hued star in the northern constellation of Cassiopeia. It is a variable star with a magnitude that ranges from 6.3 down to 8.8,[4] placing it near the limit of naked eye visibility at peak magnitude. The estimated distance to this star, as determined from its annual parallax shift of {{Val|2.0|ul=mas}},[1] is about 1,590 light years. It is moving closer to the Earth with a heliocentric radial velocity of −34 km/s.[9]This is an aging carbon star on the asymptotic giant branch.[13] Keenan (1993) assigned it a classification of {{Nowrap|C-N7 III: C2 2 Li 10}}, which indicates it is of the N star subtype in the revised Morgan–Keenan system, with a C2 strength index of 2 (a measure of the excess of carbon over oxygen) and an anomalously strong line of lithium at 6707 Å.[5] It is losing mass at the rate of {{Val|6.5e−9|u={{solar mass}} yr−1}}, which is on the low side for a star of this type. This is a semiregular variable of subtype SRb[4] with periods of 186 and 366 days due to radial pulsations.[13] It has expanded to around 600 times the Sun's radius and is radiating 17,392 times the Sun's luminosity from its photosphere at a relatively cool[24] effective temperature of 3,095 K.[14]
A magnitude 8.4 B-type visual companion, designated HD 224869, is located at an angular separation of {{Val|58|ul=arcsecond}}. The difference in the radial velocities for the two stars – 20 km/s – is too large for them to be dynamically associated.[26]
References
1. ^1 2 3 4 5 6 {{cite DR2}}
2. ^1 2 {{cite journal | title=XHIP: An extended hipparcos compilation | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | journal=Astronomy Letters | arxiv=1108.4971 | volume=38 | issue=5 | pages=331 | year=2012 | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015 }}
3. ^1 2 {{cite journal | title=General catalogue of stellar radial velocities | journal=Washington | pages=0 | last1=Wilson | first1=Ralph Elmer | date=1953 | bibcode=1953GCRV..C......0W }}
4. ^1 {{cite journal | last1=Mendoza v. | first1=Eugenio E. | last2=Johnson | first2=Harold L. | title=Multicolor Photometry of Carbon Stars | journal=The Astrophysical Journal | volume=141 | pages=161 | year=1965 | bibcode=1965ApJ...141..161M | doi=10.1086/148097 }}
5. ^1 2 3 {{cite journal | title=WZ Cas - variability on multiple time-scales | display-authors=1 | last1=Lebzelter | first1=T. | last2=Griffin | first2=R. F. | last3=Hinkle | first3=K. H. | journal=Astronomy and Astrophysics | volume=440 | issue=1 | date=September 2005 | pages=295–303 | doi=10.1051/0004-6361:20053076 | bibcode=2005A&A...440..295L }}
6. ^1 {{cite journal | title=HD 224869: an Optical Companion to WZ Cassiopeiae | last1=Herbig | first1=George H. | journal=Publications of the Astronomical Society of the Pacific | volume=67 | issue=396 | page=181 | date=June 1955 | doi=10.1086/126798 | bibcode=1955PASP...67..181H }}
7. ^1 2 3 {{cite journal | doi=10.1051/0004-6361:20020525 | bibcode=2002A&A...390..967B | title=Carbon-rich giants in the HR diagram and their luminosity function | journal=Astronomy & Astrophysics | volume=390 | issue=3 | pages=967–986 | year=2002 | last1=Bergeat | first1=J | last2=Knapik | first2=A | last3=Rutily | first3=B }}
8. ^1 2 {{cite journal | last1=Keenan | first1=P. C. | title=Revised MK Spectral Classification of the Red Carbon Stars | year=1993 | volume=105 | pages=905 | journal=Publications of the Astronomical Society of the Pacific | bibcode=1993PASP..105..905K | doi=10.1086/133252 }}
9. ^1 2 3 4 {{citation | title=General catalogue of variable stars: Version GCVS 5.1 | last1=Samus' | first1=N. N | last2=Kazarovets | first2=E. V | last3=Durlevich | first3=O. V | last4=Kireeva | first4=N. N | last5=Pastukhova | first5=E. N | journal=Astronomy Reports | volume=61 | issue=1 | pages=80 | year=2017 | postscript=. | doi=10.1134/S1063772917010085 | bibcode=2017ARep...61...80S }}
10. ^1 {{citation | title=The Violet Opacity in the Red Peculiar Stars (II). Spectral Analysis of the Cool Carbon Stars WZ CAS and V CYG | last1=Alksnis | first1=O. | last2=Zacs | first2=L. | journal=Astrophysics and Space Science | volume=215 | issue=1 | pages=73–82 | date=May 1994 | doi=10.1007/BF00627461 | bibcode=1994Ap&SS.215...73A }}