Garnet Star

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 Garnet Star, m Cep, mu Cep, HR 8316, HD 206936, SAO 33693, WDS 21435+5847A
constellation Cepheus

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

note (category: star names): Herschel's "Garnet Star". Both Bayer (1603) and Argelander (1843) showed Mu Cep in the position of 14 Cep = HR

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

position, motion, parallax:

position (J2000) RA: 21h 43min 30,4sec DEC: +58 46' 48''
position (J1900) RA: 21h 40min 26,8sec DEC: +58 19' 17''
proper motion (J2000) RA: 0,003 arcsec/a DEC: -0,003 arcsec/a
radial velocity 19 km/s
note: variable radial velocity
trigonometric parallax 0,003 arcsec


visual magnitude 4,08
(V on UBV Johnson system)

spectral / color information

spectral class M2-Ia
B-V-magnitude 2,35
U-B-magnitude 2,42
R-I-magnitude 1,76
note (category: colors): Large infrared excess.

variability information

variable star identification Mu Cep

double/multiple star system information

number of components of multiple star system 3
separation 19,5 arcsec
mag difference (of double or brightest multiple) 8,3
component ID AB

miscellaneous information

note (category: group membership): Cep OB2.

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

position, motion, parallax:

position (J2000) RA: 21h 43min 30,473sec DEC: +58 46' 48,75'' 0,35 arcsec source: 17
proper motion (J2000) RA: 0,0007 arcsec/a DEC: 0,003 arcsec/a source: 25
radial velocity 19 km/s source: 25
trigonometric parallax 0,003 - source: 25
galactic coord. (B1950) longitude: 100,6 latitude: 4,32
GCI unit vector (J2000) X: 0,429085 Y: -0,290764 Z: 0,855185


visual 3,4 (observed) source: 31
photographic 6,5 source: 16

spectral information:

spectral class M0 source: 96
Morgan-Keenan M2-Ia source: 25
B-magnitude 6,43 0,05 B-V-magnitude 2,35
U-magnitude 8,85 0,05 U-B-magnitude 2,42

variability information:

source of data: 30
variability type 192
var. amplitude 1,7
var. period 730

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 19,5 arcsec
position angle 260


16 PPM North and PPM South Catalogs and PPM Supplement
Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993
Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 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: 21h 41min 58,501sec DEC: +58 33' 0,65'' 0,026 arcsec
position (J2000) RA: 21h 43min 30,441sec DEC: +58 46' 48,1''
proper motion J1950 (FK4) RA: 0 arcsec/a DEC: 0,001 arcsec/a 0,005 arcsec/a in RA
0,004 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,0004 arcsec/a DEC: -0,003 arcsec/a
source of proper motion data Determined by source catalog


visual 4 (accuracy: 1 decimal)
source of visual magnitude data Source cited in source catalog introduction.

spectral information:

spectral class M0
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

remarks for duplicity and variability

Both double and variable, in either visual or photographic magnitudes


source catalogue GC, catalogue number: 30440
Durchmusterung BD+58 2316
Boss General Catalogue 30440
Henry Draper Catalogue 206936

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

position and proper motion:

position (J2000) RA: 21h 43,5min DEC: +58 47'
proper motion (J2000) RA: 0,005 arcsec/a DEC: 0,003 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 1878 9 260 19,5'' - 12,3 M2Iae BU 690
AC 1878 6 299 41,2'' - 12,7 - BU 690

discoverer information:

discoverer code discoverer reference
BU 690 Burnham, S.W. -


note Mu Cep. A is a semiregular variable.

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


position (J1950) RA: 22h 21min 48sec DEC: +57 25' 42'' 1 sec / 0.1 arcmin

variability informations:

variability type CEP pulsating variable star
magnitute at max. brightness 12,7
magnitute at min. brightness 14,1
photometric system photographic magnitudes
epoch for maximum light [JD] 2433541,653
17. September 1950, 03:40:19 UT
period [d] 3,76782
next maximum light [JD] 2451623,42118
19. March 2000, 22:06:30 UT
rising time 33 % of period


to a study Vol. I GCVS (see Kholopov et al. 1985-1988)
to a chart/photograph Vol. I GCVS (see Kholopov et al. 1985-1988)


ID in the GCVS catalogue 20/283
constellation Cepheus
notes on existence The star is equivalent to '0200284 MV'.

variability type description

variability type description
CEP Cepheids. Radially pulsating, high luminosity (classes Ib-II) variables with periods in the range of 1-135 days and amplitudes from several hundredths to 2 mag in V (in the B band, the amplitudes are greater). Spectral type at maximum light is F; at minimum, the types are G-K. The longer the period of light variation,the later is the spectral type. The maximum of the surface-layer expansion velocity almost coinciding with maximum light.