Alya


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 Alya, q1Ser, NSV 11557, 63 Ser, HR 7141, HD 175638, SAO 124068, FK5: 709, WDS 18562+0412A
other names Alga
constellation Serpens

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

note (category: star names): Alya; Alga.

position, motion, parallax:

position (J2000) RA: 18h 56min 13,2sec DEC: +4 12' 13''
position (J1900) RA: 18h 51min 14,9sec DEC: +4 4' 24''
proper motion (J2000) RA: 0,049 arcsec/a DEC: 0,031 arcsec/a
radial velocity -46 km/s
note: suspected variable radial velocity
rotational velocity 143 km/s (uncertain) (variable)
trigonometric parallax 0,03 arcsec
note (category: dynamical parallaxes): 0.019".

magnitude

visual magnitude 4,62
(V on UBV Johnson system)

spectral / color information

spectral class A5V
B-V-magnitude 0,17
U-B-magnitude 0,09

variability information

variable star identification 11557
note (category: variability): 4.59 - 4.72V.

double/multiple star system information

number of components of multiple star system 3
separation 22,2 arcsec
mag difference (of double or brightest multiple) 0,4
component ID AB
note (category: double and multiple data): Binary with HR 7142.

miscellaneous information

note (category: group membership): Hyades group.

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

position, motion, parallax:

position (J2000) RA: 18h 56min 13,19sec DEC: +4 12' 12,91'' 0,06 arcsec source: 15
proper motion (J2000) RA: 0,0033 arcsec/a DEC: 0,031 arcsec/a source: 25
radial velocity -46 km/s source: 25
trigonometric parallax 0,03 0,003 arcsec source: 25
galactic coord. (B1950) longitude: 37,22 latitude: 0,85
GCI unit vector (J2000) X: 0,242199 Y: -0,967454 Z: 0,073301

magnitude:

visual 4,61 (observed) source: 25
photovisual 4,5 source: 2

spectral information:

spectral class A5 source: 96
Morgan-Keenan A5V source: 25
B-magnitude 4,77 0,05 B-V-magnitude 0,16
U-magnitude 4,88 0,05 U-B-magnitude 0,11

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 22,3 arcsec
magnitude difference between brightest and second brightest component 0,36
position angle 104

component magnitude spectral class catalogue(s)/name(s)
A 4,61 A5 Alya, q1Serpentis, 63 Ser, HR 7141, HD 175638, SAO 124068
B 4,98 A5 q2Serpentis, 63 Ser, HR 7142, HD 175639, SAO 124070

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: 18h 53min 43,976sec DEC: +4 8' 13,25'' 0,004 arcsec
position (J2000) RA: 18h 56min 13,192sec DEC: +4 12' 12,92''
proper motion J1950 (FK4) RA: 0,0031 arcsec/a DEC: 0,032 arcsec/a 0,001 arcsec/a in RA
0,001 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,0033 arcsec/a DEC: 0,031 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 the "Henry Draper Catalogue".

spectral information:

spectral class A5
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue FK4, catalogue number: 709
Durchmusterung BD+04 3916
Boss General Catalogue 25991
Henry Draper Catalogue 175638

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

position and proper motion:

position (J2000) RA: 18h 56,2min DEC: +4 12'
proper motion (J2000) RA: 0,049 arcsec/a DEC: 0,031 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 1822 often 104 21,6'' 4,62 4,98 A5V A5Vn STF2417
1984 - 22,3''
BC 1927 2 56 14,1'' 4,98 7,9 A5Vn STF2417
1954 58 26''

discoverer information:

discoverer code discoverer reference
STF2417 Struve, F.G.W. -

notes:

note Theta (1) Ser. B is BD+04@3917, Theta (2) Ser.

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

position:

position (J1950) RA: 18h 53min 44sec DEC: +4 8' 13''

variability informations:

magnitute at max. brightness 4,59
magnitute at min. brightness 4,72
photometric system visual, photovisual or Johnson's V

spectral information

spectral class A5

references

to a study 290477D (designation: ZI 1555)

miscanellous

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