Unukalhai


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


catalogues and names Unukalhai, a Ser, NSV 20391, 24 Ser, HR 5854, HD 140573, SAO 121157, FK5: 582, WDS 15443+0626A
other names Unuk al Hay, Unuk Elhaia, Unuk, Unukalhay, Cor Serpentis
constellation Serpens

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

note (category: star names): UNUKALHAI; Unuk al Hay; Unuk Elhaia; Unuk; Unukalhay; Cor Serpentis.

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

position, motion, parallax:

position (J2000) RA: 15h 44min 16,1sec DEC: +6 25' 32''
position (J1900) RA: 15h 39min 20,5sec DEC: +6 44' 25''
proper motion (J2000) RA: 0,137 arcsec/a DEC: 0,047 arcsec/a
radial velocity 3 km/s
note: suspected variable radial velocity
rotational velocity <17 km/s (uncertain) (variable)
trigonometric parallax 0,053 arcsec

magnitude

visual magnitude 2,65
(V on UBV Johnson system)

spectral / color information

spectral class K2IIIbCN1
B-V-magnitude 1,17
U-B-magnitude 1,24
R-I-magnitude 0,56

double/multiple star system information

number of components of multiple star system 3
separation 58,2 arcsec
mag difference (of double or brightest multiple) 8,3
component ID AB
note (category: double and multiple data): SR? Amp. 0.2V. ADS 9765B, optical.

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

position, motion, parallax:

position (J2000) RA: 15h 44min 16,087sec DEC: +6 25' 32,31'' 0,06 arcsec source: 15
proper motion (J2000) RA: 0,0092 arcsec/a DEC: 0,047 arcsec/a source: 25
radial velocity 3 km/s source: 25
trigonometric parallax 0,053 0,005 arcsec source: 25
galactic coord. (B1950) longitude: 14,2 latitude: 44,08
GCI unit vector (J2000) X: -0,554716 Y: -0,824479 Z: 0,111914

magnitude:

visual 2,65 (observed) source: 25
photovisual 2,8 source: 2

spectral information:

spectral class K0 source: 96
Morgan-Keenan K2IIIbCN1 source: 25
B-magnitude 3,82 0,05 B-V-magnitude 1,17
U-magnitude 5,06 0,05 U-B-magnitude 1,24

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 58,2 arcsec
magnitude difference between brightest and second brightest component 9,1
position angle 350

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
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: 15h 41min 48,151sec DEC: +6 34' 53,93'' 0,003 arcsec
position (J2000) RA: 15h 44min 16,092sec DEC: +6 25' 32,34''
proper motion J1950 (FK4) RA: 0,0091 arcsec/a DEC: 0,044 arcsec/a 0,001 arcsec/a in RA
0,001 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,0092 arcsec/a DEC: 0,047 arcsec/a
source of proper motion data Determined by source catalog

magnitude:

visual 2,8 (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: 582
Durchmusterung BD+06 3088
Boss General Catalogue 21158
Henry Draper Catalogue 140573

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

position and proper motion:

position (J2000) RA: 15h 44,3min DEC: +6 26'
proper motion (J2000) RA: 0,137 arcsec/a DEC: 0,047 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 1836 8 360 61,5'' 2,65 11,8 K2III HJ 1277
1911 350 58,2''
AC 1836 2 271 112,7'' 2,65 13 - HJ 1277
1960 268 136,1''

discoverer information:

discoverer code discoverer reference
HJ 1277 Herschel, J. -

notes:

note Alpha Ser. Variable?