Star in the constellation Cassiopeia
υ1 Cassiopeiae
Location of υ
1 Cassiopeiae (circled)
Observation dataEpoch J2000.0 Equinox J2000.0 (ICRS )
Constellation
Cassiopeia [ 1]
Right ascension 00h 55m 00.15523s [ 2]
Declination
+58° 58′ 21.7108″[ 2]
Apparent magnitude (V)4.82[ 3]
Characteristics
Evolutionary stage
red clump [ 4]
Spectral type
K2 III[ 5]
U−B color index
+1.25[ 3]
B−V color index
+1.21[ 3]
Astrometry Radial velocity (Rv )−23.57[ 6] km/s Proper motion (μ) RA: ± 0.36[ 2] mas /yr Dec.: ± 0.33[ 2] mas /yr Parallax (π)9.93± 0.49 mas [ 2] Distance 330 ± 20 ly pc ) Absolute magnitude (MV )−0.644[ 6] Details Mass 1.39[ 7] M ☉ Radius 21[ 8] R ☉ Luminosity 174[ 7] L ☉ Surface gravity (log g )1.76[ 6] cgs Temperature ± 14[ 7] K Metallicity [Fe/H] −0.25[ 6] dex Rotational velocity (v sin i )1.1[ 9] Age 4.75[ 7] Gyr Other designations υ1 Cas , 26 Cas , BD +58°134HD 5234HIP 4292HR 253SAO 21832ADS 748CCDM J00551+5858WDS J00550+5858A[ 10] Database references SIMBAD data
υ1 Cassiopeiae is the bright star in the lower right. The bright star in the upper left is υ2 Cassiopeiae. Upsilon1 Cassiopeiae (υ1 Cassiopeiae) is an astrometric binary [ 11] constellation of Cassiopeia . It is visible to the naked eye with an apparent visual magnitude of 4.82.[ 3] parallax shift of 9.93 mas as seen from Earth,[ 2] light years from the Sun .
The visible component is an evolved K-type giant star with a stellar classification of K2 III.[ 5] [ 7] red clump star that is generating energy through the fusion of helium at its core.[ 4] angular diameter , after correction for limb darkening , is ± 0.02 mas [ 12] radius of the Sun .[ 8] mass of the Sun and is radiating 174 times the Sun's luminosity from its expanded photosphere at an effective temperature of 4,422 K.[ 7]
There is a magnitude 12.50 visual companion at an angular separation of 17.80 arc seconds along a position angle of 61°, as of 2003. A more distant magnitude 12.89 companion lies at a separation of 93.30 arc seconds along a position angle of 125°, as measured in 2003. Neither star appears to be physically associated with υ1 Cas.[ 13]
^ Anderson, E.; Francis, Ch. (May 2012), "XHIP: An extended hipparcos compilation", Astronomy Letters , 38 (5): 331– 346, arXiv :1108.4971 Bibcode :2012AstL...38..331A , doi :10.1134/S1063773712050015 , eISSN 1562-6873 , ISSN 1063-7737 , S2CID 119257644 . ^ 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 , S2CID 18759600 . ^ a b c d Argue, A. N. (1966), "UBV photometry of 550 F, G and K type stars", Monthly Notices of the Royal Astronomical Society , 133 (4): 475, Bibcode :1966MNRAS.133..475A , doi :10.1093/mnras/133.4.475 ^ a b Valentini, M.; Munari, U. (November 2010), "A spectroscopic survey of faint, high-Galactic-latitude red clump stars. I. The high resolution sample" , Astronomy and Astrophysics , 522 : A79, arXiv :1007.0207 Bibcode :2010A&A...522A..79V , doi :10.1051/0004-6361/201014870 , S2CID 119156545 . [permanent dead link ^ a b Eggen, O. J. (1962), "Space-velocity vectors for 3483 stars with proper motion and radial velocity", Royal Observatory Bulletin , 51 : 79, Bibcode :1962RGOB...51...79E . ^ a b c d Soubiran, C.; et al. (2008), "Vertical distribution of Galactic disk stars. IV. AMR and AVR from clump giants", Astronomy and Astrophysics , 480 (1): 91– 101, arXiv :0712.1370 Bibcode :2008A&A...480...91S , doi :10.1051/0004-6361:20078788 , S2CID 16602121 . ^ a b c d e f Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal , 150 (3): 23, arXiv :1507.01466 Bibcode :2015AJ....150...88L , doi :10.1088/0004-6256/150/3/88 , S2CID 118505114 , 88. ^ a b Lang, Kenneth R. (2006), Astrophysical formulae Birkhäuser , ISBN 3-540-29692-1 * ) is given by:
2
⋅
R
∗
=
(
101
⋅
1.97
⋅
10
−
3
)
AU
0.0046491
AU
/
R
⨀
≈
42.8
⋅
R
⨀
{\displaystyle {\begin{aligned}2\cdot R_{*}&={\frac {(101\cdot 1.97\cdot 10^{-3})\ {\text{AU}}}{0.0046491\ {\text{AU}}/R_{\bigodot }}}\\&\approx 42.8\cdot R_{\bigodot }\end{aligned}}}
^ De Medeiros, J. R.; et al. (November 2000), "Rotation and lithium in single giant stars", Astronomy and Astrophysics , 363 : 239– 243, arXiv :astro-ph/0010273 Bibcode :2000A&A...363..239D . ^ "ups01 Cas" . SIMBAD Centre de données astronomiques de Strasbourg . Retrieved 2017-08-30 .^ 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 . ^ Richichi, A.; et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics , 431 (2): 773– 777, Bibcode :2005A&A...431..773R , doi :10.1051/0004-6361:20042039 ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal , 122 (6): 3466, Bibcode :2001AJ....122.3466M , doi :10.1086/323920
