Sham


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 Sham, a Sge, 5 Sge, HR 7479, HD 185758, SAO 105120, WDS 19401+1801A
other names Alsahm
constellation Sagitta

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

note (category: star names): Sham; Alsahm. Names originally corresponded to whole constellation Sagitta.

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

position, motion, parallax:

position (J2000) RA: 19h 40min 5,8sec DEC: +18° 0' 50''
position (J1900) RA: 19h 35min 37,5sec DEC: +17° 47' 2''
proper motion (J2000) RA: 0,014 arcsec/a DEC: -0,021 arcsec/a
radial velocity 2 km/s
note: suspected variable radial velocity
rotational velocity 0 km/s (uncertain) (variable)

magnitude

visual magnitude 4,37
(V on UBV Johnson system)

spectral / color information

spectral class G1II
B-V-magnitude 0,78
U-B-magnitude 0,43
R-I-magnitude 0,37

double/multiple star system information

number of components of multiple star system 4
separation 90 arcsec
mag difference (of double or brightest multiple) 6,8
component ID AD
note (category: double and multiple data): Companions B and C optical.

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

position, motion, parallax:

position (J2000) RA: 19h 40min 5,775sec DEC: +18° 0' 50'' ±0,2 arcsec source: 52
proper motion (J2000) RA: 0,0005 arcsec/a DEC: -0,02 arcsec/a source: 25
radial velocity 2 km/s source: 25
galactic coord. (B1950) longitude: 54,46° latitude: -2,14°
GCI unit vector (J2000) X: 0,402264 Y: -0,861713 Z: 0,309248

magnitude:

visual 4,37 (observed) source: 25
photovisual 4,4 source: 2
photographic 5,1 source: 16

spectral information:

spectral class G0 source: 96
Morgan-Keenan G1II source: 25
B-magnitude 5,15 ±0,05 B-V-magnitude 0,78
U-magnitude 5,58 ±0,05 U-B-magnitude 0,43

double/multiple star system information:

source of data: 19
separation between brightest and second brightest component 30,8 arcsec
magnitude difference between brightest and second brightest component 8,8
position angle 179 °

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
52 PPMN-HP subset
PPMN Star Catalogue (Reference 16) High-Precision Subset (Code H)
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: 19h 37min 51,612sec DEC: +17° 53' 51,21'' ±0,015 arcsec
position (J2000) RA: 19h 40min 5,779sec DEC: +18° 0' 49,69''
proper motion J1950 (FK4) RA: 0,0009 arcsec/a DEC: -0,02 arcsec/a ±0,002 arcsec/a in RA
±0,002 arcsec/a in DEC
proper motion J2000 (FK5) RA: 0,001 arcsec/a DEC: -0,021 arcsec/a
source of proper motion data Determined by source catalog

magnitude:

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

spectral information:

spectral class G0
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: 27215
Durchmusterung BD+17 4042
Boss General Catalogue 27215
Henry Draper Catalogue 185758

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

position and proper motion:

position (J2000) RA: 19h 40,1min DEC: +18° 1'
proper motion (J2000) RA: 0,02 arcsec/a DEC: -0,021 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 1910 4 180° 33'' 4,37 13,2 G1III J 121
1985 179° 30,8''
AC 1910 1 249° 35,8'' 4,37 14,9 - J 121

discoverer information:

discoverer code discoverer reference
J 121 Jonckheere, R. -

notes:

note Alpha Sge.