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Norwegian Astronomical Society - Variable Star Section
***** Sequence for the Supergiant Variable Star Rho Cassiopeiae *****
Compiled by Bjorn H. Granslo (version 2003 August 14)
2349+56 Rho Cas [R.A. = 23h54m23s.0, Decl. = +57o29'58" (2000.0)]
Rho Cas = HR 9045 = HD 224014 = TYC 4009-2605. GCVS (Kholopov et al.
1998) has type SRD, mag. 4.1 - 6.2 V, period 320 days and spectral
type F8pIa-K0pIa-0. According to AAVSO is Rho Cas normally at visual
magnitude 4.4-5.0, but has shown several fading episodes, the last one
in 2000 to mag. 5.5. GCPD (Mermilliod et al.) has V = 4.47 (+/- 0.07)
and B-V = +1.13 (+/- 0.06), mean of 7 measurements.
Other variable stars within 7 deg. from Rho Cas and with visual
maximum magnitude brighter than 8.0 and amplitude > 0.2 mag. include
R Cas, T Cas, V Cas, SV Cas, TV Cas, WZ Cas, V373 Cas, V436 Cas and
V705 Cas (Nova 1993).
*** 1. Sequence Stars for the Field of Rho Cassiopeiae ***
This list contains identifications, positions and photometry (V, B-V)
for comparison stars with B-V from -0.2 to 0.5. Although several of
these stars appear to be somewhat variable they should be usable as
comparisons for visual observations. Star R may serve as a nearby
reference for differential photometry (V and/or B) with PEP/CCD.
Identifications of stars A-E and H are due to BAA.VSS, others are
NAS.VSS. All stars, except C, are located within 7.5 deg. from Rho Cas.
Id R.A. (2000.0) Decl. Star Name V-mag sV B-V sB-V Source
h m s o ' "
A 00 36 58.3 +53 53 49 Zeta Cas 3.67 0.01 -0.20 0.01 GCPD
B 00 33 00.0 +62 55 54 Kappa Cas 4.16 0.02 0.13 0.02 GCPD
C 01 11 06.2 +55 09 00 Theta Cas 4.33 0.01 0.17 0.01 GCPD
D 00 31 46.4 +54 31 20 Lambda Cas 4.73 0.01 -0.10 0.01 GCPD
E 23 59 00.5 +55 45 18 Sigma Cas 4.89 0.01 -0.08 0.02 GCPD
F 00 36 08.3 +54 10 06 HR 144 5.07 0.02 -0.10 0.01 GCPD
G 00 24 47.5 +61 49 52 12 Cas 5.39 0.01 0.00 0.01 GCPD
H 23 57 08.5 +55 42 21 HR 9059 5.56 0.01 0.48 0.02 GCPD
K 00 04 13.7 +62 17 16 9 Cas 5.89 0.01 0.27 0.02 GCPD
L 23 49 11.9 +58 57 48 HR 9020 6.36 0.04 0.40 0.01 GCPD
M 00 04 55.0 +58 31 56 HD 225257 6.61 0.02 0.04 0.02 GCPD
N 23 57 47.2 +57 08 23 HD 224425 7.31 0.02 0.22 0.02 GCPD
P 23 51 38.5 +57 12 27 HD 223694 8.01 0.02 0.44 0.02 Tycho-2
R 23 54 07.2 +57 12 00 HD 223980 8.45 0.02 0.08 0.02 Tycho-2
Notes on photometry:
Stars A-N: V magnitudes and B-V colours are derived from data obtained
at GCPD, The Lausanne Photometric Database [GCPD].
Stars P and R: V magnitudes and B-V colours are derived from Tycho-2
BT and VT photometry (Hog et al. 2000) by using the correction
procedure of Bessell (2000).
Other notes:
Star A: HR 153 = HD 3360 = TYC 3654-2132. Possible variable NSV 225,
Bouigue (1959) has V = 3.59, other measurements have V = 3.66-3.68.
Star B: HR 130 = HD 2905 = TYC 4019-3949. Kappa Cas is variable, type
ACYG [GCVS], mag. 4.14 - 4.20 V [GCPD].
Star C: HR 343 = HD 6961 = TYC 3673-1923. Annual proper motion 0".227
in p.a. 95 deg. [HIP], position is given for epoch 2000.0. Possible
variable NSV 423, mag. 4.32 - 4.36 V [NSV].
Star D: HR 123 = HD 2772 = TYC 3658-2414. Double star STT 12, mag. 5.5
and 5.8, sep. 0".5 [WDS]; combined V and B-V is given in sequence.
Possible variable NSV 15106 and Eggen (1963) has V = 4.90.
Star E: HR 9071 = HD 224572 = ADS 17140 = TYC 4005-2471 & 4005-2470.
Double star STF 3049, mag. 5.0 and 7.0, sep. 3".1 [WDS]; combined
photometry is given in sequence.
Star F: HD 3240 = TYC 3654-2131.
Star G: HR 93 = HD 2011 = TYC 4015-3523.
Star H: HD 224355 = TYC 4005-1055. Possible variable NSV 14773, type
E:, amplitude 0.05 mag. [NSV].
Star K: HR 9100 = HD 225180 = TYC 4018-3891. Possible variable
NSV 15009.
Star L: HD 223421 = TYC 4013-1801. GCPD data indicate a variability of
0.08 mag.
Star M: TYC 3664-0929/3664-1989. Double star STF 3057, mag. 6.6 and
8.7, sep. 3".7 [WDS]; combined photometry given in sequence.
Star N: TYC 4009-2066. 35'.0 from Rho Cas.
Star P: TYC 4009-0822. V = 8.015 (Olsen 1983). 28'.3 from Rho Cas.
Star R: TYC 4009-0607. 18'.1 from Rho Cas.
*** 2. Other Reference Stars ***
These stars - located within 2 deg. of Rho Cas - may be used as
colour calibrators:
Id R.A. (2000.0) Decl. Star Name V-mag sV B-V sB-V Source
h m s o ' "
X 23 47 03.5 +58 39 07 Tau Cas 4.87 0.02 1.12 0.02 GCPD
Y 23 47 01.9 +57 27 05 HR 9010 5.52 0.02 1.67 0.03 GCPD
Z 23 54 02.0 +56 29 22 HD 223969 7.15 0.02 1.65 0.03 Tycho-2
Notes:
Star X and Y: See note for stars A-N under sequence stars.
Star X: HR 9008 = HD 223165 = TYC 4013-1825. Possible variable
NSV 14707, NSV has an uncertain amplitude of 0.3 mag., but other
sources (HIP, TYC, GCPD) indicate a variation of < 0.1 magnitude.
Star Y: HD 223173 = TYC 4009-2606. Possible variable NSV 26143.
Tycho-2 w/Bessell has V = 5.50 (+/- 0.02) and B-V = 1.65 (+/-0.02).
Star Z: TYC 4009-2166. See note for stars P and R under sequence stars.
Acknowledgements:
The VizieR Service at Centre de Donnees astronomiques de Strasbourg
and The Lausanne General Catalogue of Photometric Data (GCPD) web
sites have been used in preparing this sequence.
References:
Bessell M.: 2000, "The Hipparcos and Tycho Photometric System
Passbands", Publ. Ast. Soc. Pacific, 112, 961.
Bouigue R.: 1959, "Contribution aux recherches de photometrie
photoelectrique dans la galaxie. I, II, III, IV, V", Ann. Obs.
Toulouse, 27, 47.
Eggen O. J.: 1963, "Luminosities, Colors, and Motions of the brightest
A-type Stars", Astron. Journ., 68, 697.
Hog E. et al.: 2000, "The Tycho-2 Catalogue of the 2.5 Million
Brightest Stars", Astron. Astrophys. 355, L27. [Tycho-2, TYC]
Kazarovets E. V., Durlevich O. V., Samus N. N.: 1998, "New Catalogue
of Suspected Variable Stars. Supplement - Version 1.0", Institute of
Astronomy of Russian Academy of Sciences and Sternberg Astronomical
Institute [NSV].
Kholopov P. N. et al.: 1998, "Combined General Catalogue of Variable
Stars, 4.1 Edition". The most updated version of GCVS is at
http://www.sai.msu.su/groups/cluster/gcvs/gcvs/ [GCVS].
Mermilliod J.-C., Hauck B., Mermilliod M.: "The General Catalogue of
Photometric Data", University of Lausanne, Switzerland.
URL: http://obswww.unige.ch/gcpd/gcpd.html [GCPD].
Olsen E. H.: 1983, "Four-Colour ubvy and H-beta Photometry of A5 to G0
Stars brighter than 8m.3", Astron. Astrophys. Suppl. Ser., 54, 55.
Perryman M. A. C.; ESA: 1997, The Hipparcos Catalogue, ESA SP Series,
Vol. 1200 [HIP].
Worley C. E., Douglass G. G.: 1996, "The Washington Visual Double Star
Catalog, 1996.0", US Naval Observatory [WDS].
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