Diadem


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 (suspected variables)


catalogues and names Diadem, a Com, NSV 06116, 42 Com, HR 4968, HD 114378, SAO 100443, WDS 13100+1732A
constellation Coma Berenices

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

note (category: star names): Diadem.

position, motion, parallax:

position (J2000) RA: 13h 9min 59,3sec DEC: +17° 31' 46''
position (J1900) RA: 13h 5min 7,4sec DEC: +18° 3' 30''
proper motion (J2000) RA: -0,431 arcsec/a DEC: 0,136 arcsec/a
radial velocity -18 km/s
note: suspected variable radial velocity
rotational velocity 28 km/s (uncertain) (variable)
trigonometric parallax 0,054 arcsec
note (category: radial and/or rotational velocities): Probably blended with HR 4969.
note (category: dynamical parallaxes): 0.058".

magnitude

visual magnitude 5,22
(original HR magnitude)

spectral / color information

spectral class F5V
B-V-magnitude 0,45
U-B-magnitude -0,06
note (category: spectra): Spectrum blended with HR 4969.

variability information

variable star identification 6116
note (category: variability): Var. of combined light with HR 4969 not confirmed, but 90d inclination of orbit indicates eclipses possible.

double/multiple star system information

number of components of multiple star system 3
separation 0,2 arcsec
mag difference (of double or brightest multiple) 0,1
component ID AB
note (category: double and multiple data): AB 5.05 F5V, 5.08 F5V, 25.87y, a = 0.662". Colors, spectrum for combined light. Mag. of blended HR 4968, 4969 is 4.32V. ADS 8804A speckle interferometric sep. 0.43" 1978.40, 0.58" 1981.47.

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

position, motion, parallax:

position (J2000) RA: 13h 9min 59,331sec DEC: +17° 31' 45,92'' ±0,43 arcsec source: 16
proper motion (J2000) RA: -0,0294 arcsec/a DEC: 0,143 arcsec/a source: 25
radial velocity -18 km/s source: 25
trigonometric parallax 0,054 ±0,005 arcsec source: 25
galactic coord. (B1950) longitude: 327,99° latitude: 79,49°
GCI unit vector (J2000) X: -0,909443 Y: -0,286697 Z: 0,301196

magnitude:

visual 5,05 (observed) source: 25
photovisual 5,2 source: 2
photographic 4,6 source: 16

spectral information:

spectral class F5 source: 96
Morgan-Keenan F5V source: 25
B-magnitude 5,5 ±0,05 B-V-magnitude 0,45
U-magnitude 5,44 ±0,05 U-B-magnitude -0,06

double/multiple star system information:

source of data: 19
magnitude difference between brightest and second brightest component 0

component magnitude spectral class catalogue(s)/name(s)
A 5,05 F5 Diadem, a Comae Berenices, 42 Com, HR 4968, HD 114378, SAO 100443
B 5,08 F5 a Comae Berenices, 42 Com, HR 4969, HD 114379, SAO 100443

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
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
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
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: 13h 7min 33,321sec DEC: +17° 47' 36,25'' ±0,014 arcsec
position (J2000) RA: 13h 9min 59,287sec DEC: +17° 31' 45,73''
proper motion J1950 (FK4) RA: -0,0302 arcsec/a DEC: 0,131 arcsec/a ±0,002 arcsec/a in RA
±0,002 arcsec/a in DEC
proper motion J2000 (FK5) RA: -0,0301 arcsec/a DEC: 0,136 arcsec/a
source of proper motion data Determined by source catalog

magnitude:

visual 4,5 (accuracy: 2 decimals)
source of visual magnitude data Taken from Harvard or San Luis photometry.

spectral information:

spectral class F5
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

remarks for duplicity and variability

Double star in Aitken's Double Star Catalogue (Aitken 1932)

catalogues

source catalogue GC, catalogue number: 17833
Durchmusterung BD+18 2697
Boss General Catalogue 17833
Henry Draper Catalogue 114378
The "SAO Catalog" entry refers to two consecutive HD numbers, the lower of which is given.

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

position and proper motion:

position (J2000) RA: 13h 10min DEC: +17° 32'
proper motion (J2000) RA: -0,436 arcsec/a DEC: 0,138 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 1827 often ° '' 5,1 5,1 F6V STF1728
AB-C 1851 6 322° 135,6'' 5,2 10,2 - STF1728
1923 330° 110,3''

discoverer information:

discoverer code discoverer reference
STF1728 Struve, F.G.W. -

notes:

note Alpha Com. P = 25.8yr., a = 0.668", inclination 90 degrees.

data from Combined General Catalogue of Variable Stars (suspected variables) (Kholopov+ 1998)

position:

position (J1950) RA: 13h 7min 33,3sec DEC: +17° 47' 36''

variability informations:

magnitute at max. brightness 4,29
magnitute at min. brightness 4,35
photometric system visual, photovisual or Johnson's V

spectral information

spectral class F6

references

to a study 482315D (designation: 42 COM)

miscanellous

There are notes in the published catalog (Kukarkin et al.(1982)).