g2Delphini


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 g2Del, 12 Del, HR 7948, HD 197964, SAO 106476, FK5: 1541, WDS 20467+1607A
constellation Delphinus

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


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

position, motion, parallax:

position (J2000) RA: 20h 46min 39,5sec DEC: +16 7' 27''
position (J1900) RA: 20h 42min 1,1sec DEC: +15 45' 50''
proper motion (J2000) RA: -0,032 arcsec/a DEC: -0,197 arcsec/a
radial velocity -7 km/s
note: suspected variable radial velocity
rotational velocity 0 km/s (uncertain) (variable)
trigonometric parallax 0,026 arcsec
note (category: dynamical parallaxes): 0.033".

magnitude

visual magnitude 4,27
(V on UBV Johnson system)

spectral / color information

spectral class K1IV
B-V-magnitude 1,04
U-B-magnitude 0,97
R-I-magnitude 0,48

double/multiple star system information

separation 9,8 arcsec
mag difference (of double or brightest multiple) 1
note (category: double and multiple data): See HR 7947.

miscellaneous information

note (category: group membership): Wolf 630 group.

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

position, motion, parallax:

position (J2000) RA: 20h 46min 39,499sec DEC: +16 7' 27,43'' 0,06 arcsec source: 15
proper motion (J2000) RA: -0,0022 arcsec/a DEC: -0,197 arcsec/a source: 25
radial velocity -7 km/s source: 25
trigonometric parallax 0,026 0,003 arcsec source: 25
galactic coord. (B1950) longitude: 61,5 latitude: -16,58
GCI unit vector (J2000) X: 0,638618 Y: -0,717662 Z: 0,277722

magnitude:

visual 4,27 (observed) source: 25
photovisual 4,5 source: 2

spectral information:

spectral class G5 source: 96
Morgan-Keenan K1IV source: 25
B-magnitude 5,31 0,05 B-V-magnitude 1,04
U-magnitude 6,28 0,05 U-B-magnitude 0,97

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 9,6 arcsec
magnitude difference between brightest and second brightest component 0,87
position angle 267

component magnitude spectral class catalogue(s)/name(s)
A 4,27 G5 g2Delphini, 12 Del, HR 7948, HD 197964, SAO 106476
B 5,14 F8 g1Delphini, 12 Del, HR 7947, HD 197963, SAO 106475

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: 20h 44min 20,236sec DEC: +15 56' 34,82'' 0,006 arcsec
position (J2000) RA: 20h 46min 39,49sec DEC: +16 7' 27,39''
proper motion J1950 (FK4) RA: -0,0024 arcsec/a DEC: -0,195 arcsec/a 0,001 arcsec/a in RA
0,001 arcsec/a in DEC
proper motion J2000 (FK5) RA: -0,0023 arcsec/a DEC: -0,198 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 G5
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue FK4, catalogue number: 1541
Durchmusterung BD+15 4255A
Boss General Catalogue 28966
Henry Draper Catalogue 197964

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

position and proper motion:

position (J2000) RA: 20h 46,7min DEC: +16 7'
proper motion (J2000) RA: -0,032 arcsec/a DEC: -0,197 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
- 1823 often 274 11,9'' 4,27 5,14 K1IV F7V STF2727
1988 267 9,6''

discoverer information:

discoverer code discoverer reference
STF2727 Struve, F.G.W. -

notes:

note Gamma Del. A premature orbit has been computed.