Schedar


The object was found in the following catalogues:
  1. The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

  2. SKY2000 - Master Star Catalog

  3. Smithsonian Astrophysical Observatory Star Catalog

  4. The Washington Visual Double Star Catalog, 1996.0

  5. Combined General Catalogue of Variable Stars (Vol. I-III)


catalogues and names Schedar, a Cas, alf Cas, 18 Cas, HR 168, HD 3712, SAO 21609, FK5: 21, WDS 00405+5632A
other names Shedir, Schedir
constellation Cassiopeia

data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)

note (category: star names): SHEDIR; Schedar; Schedir.

object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

position, motion, parallax:

position (J2000) RA: 0h 40min 30,5sec DEC: +56° 32' 14''
position (J1900) RA: 0h 34min 49,7sec DEC: +55° 59' 20''
proper motion (J2000) RA: 0,053 arcsec/a DEC: -0,032 arcsec/a
radial velocity -4 km/s
note: suspected variable radial velocity
rotational velocity 21 km/s (uncertain) (variable)
trigonometric parallax 0,016 arcsec

magnitude

visual magnitude 2,23
(V on UBV Johnson system)

spectral / color information

spectral class K0IIIa
B-V-magnitude 1,17
U-B-magnitude 1,13
R-I-magnitude 0,6

variability information

variable star identification Alp Cas
note (category: variability): Cst 2.20 - 2.27V.

double/multiple star system information

number of components of multiple star system 4
separation 64,4 arcsec
mag difference (of double or brightest multiple) 6,7
component ID AD
note (category: double and multiple data): D is 8.5v K2IV-V, vsini <54k/s. All components probably optical.

data from SKY2000 - Master Star Catalog (Myers+ 1997)

position, motion, parallax:

position (J2000) RA: 0h 40min 30,45sec DEC: +56° 32' 14,46'' ±0,06 arcsec source: 15
proper motion (J2000) RA: 0,0064 arcsec/a DEC: -0,032 arcsec/a source: 25
radial velocity -4 km/s source: 25
trigonometric parallax 0,016 ±0,002 arcsec source: 25
galactic coord. (B1950) longitude: 121,42° latitude: -6,3°
GCI unit vector (J2000) X: 0,542803 Y: 0,096951 Z: 0,834245

magnitude:

visual 2,2 (observed) source: 31
photovisual 2,5 source: 2

spectral information:

spectral class K0 source: 96
Morgan-Keenan K0-IIIa source: 25
B-magnitude 3,4 ±0,05 B-V-magnitude 1,17
U-magnitude 4,53 ±0,05 U-B-magnitude 1,13

variability information:

source of data: 30
variability type 999
var. amplitude 0,07

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 19,8 arcsec
magnitude difference between brightest and second brightest component 11,5
position angle 275 °

component magnitude spectral class catalogue(s)/name(s)
A 2,2 K0 Schedar, a Cassiopeiae, 18 Cas, HR 168, HD 3712, SAO 21609
B 8,784 K0

sources:

2 HD and HDE Catalogs
Cannon, A.J., and E.C. Pickering, Harvard Annals, Vols 91-99, 1918-24, Cambridge, Massachusetts: Harvard University; Cannon, A.J., Harvard Annals, Vol. 100, 1925-36, Cambridge, Massachusetts: Harvard University; and Cannon, A.J., and M. Walton Mayall, Harvard Annals, Vol. 112, 1949, Cambridge, Massachusetts: Harvard University
15 FK5, FK5 Extension and FK5 Supplement
Fricke, W., H. Schwan and T. Lederle, "Fifth Fundamental Catalogue (FK5), Part I. The Basic Fundamental Stars," Veroff. Astronomisches Recheninstitut, No. 32, Heidelberg, Germany, 1988, and Fricke, W., H. Schwan, and T.E. Corbin, "Fifth Fundamental Catalogue (FK5), Part II. The FK5 Extension," Veröff. Astronomisches Recheninstitut, No. 33, Heidelberg, Germany, 1991
19 WDS Catalog
Worley, C.E., and G.G. Douglass, Washington Catalog of Visual Double Stars 1996.0, United States Naval Observatory, 1996
25 Bright Star Catalogue, 5th edition
Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 1994
30 GCVS, 4th edition
Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88
31 CRM' (non-GCVS variable data)
Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994
96 SAO or HD/HDE Catalog
Reference from Value 1 or Reference from Value 2

data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)

position and proper motion:

position (J1950) RA: 0h 37min 39,313sec DEC: +56° 15' 48,6'' ±0,003 arcsec
position (J2000) RA: 0h 40min 30,465sec DEC: +56° 32' 14,43''
proper motion J1950 (FK4) RA: 0,0064 arcsec/a DEC: -0,027 arcsec/a ±0,001 arcsec/a in RA
±0,001 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,0065 arcsec/a DEC: -0,032 arcsec/a
source of proper motion data Determined by source catalog

magnitude:

visual 2,5 (accuracy: 2 decimals)
source of visual magnitude data Taken from the "Henry Draper Catalogue".

spectral information:

spectral class K0
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue FK4, catalogue number: 21
Durchmusterung BD+55 139
Boss General Catalogue 792
Henry Draper Catalogue 3712

data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)

position and proper motion:

position (J2000) RA: 0h 40,5min DEC: +56° 32'
proper motion (J2000) RA: 0,053 arcsec/a DEC: -0,032 arcsec/a

double/multiple star system information:

component year number of measures position angle angular separation magnitude of 1st component magnitude of 2nd component spectral class(es) discoverer code
AB 1889 2 272° 17,6'' 2,5 14 K0IIIa BU 1349
1934 275° 19,8''
AC 1878 4 109° 40,1'' 2,5 13 - BU 1349
1908 105° 38,3''
AD 1781 11 275° 56,2'' 2,5 8,5 - H 18
1913 280° 64,4''

discoverer information:

discoverer code discoverer reference
BU 1349 Burnham, S.W. -
H 18 Herschel, W. -

notes:

note Alpha Cas. AD: H V 18. Also HJ 1993.

data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)

position:

position (J1950) RA: 0h 37min 39,3sec DEC: +56° 15' 49''

variability informations:

variability type CST:
magnitute at max. brightness 2,2
magnitute at min. brightness 2,27
photometric system visual, photovisual or Johnson's V

spectral information

spectral class K0IIIa

references

to a chart/photograph no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue 18/9001
constellation Cassiopeia
notes on existence The star is equivalent to '0189002 bet'.
There are notes in published catalog.

variability type description

variability type description
CST Nonvariable stars, formerly suspected to be variable and hastily designated. Further observations have not confirmed their variability.