g Equulei
catalogues and names | g Equ, gam Equ, 5 Equ, HR 8097, HD 201601, SAO 126593, FK5: 1555, WDS 21103+1008A |
constellation | Equuleus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
position (J2000) | RA: 21h 10min 20,5sec | DEC: +10° 7' 54'' |
position (J1900) | RA: 21h 5min 28,7sec | DEC: +9° 43' 43'' |
proper motion (J2000) | RA: 0,057 arcsec/a | DEC: -0,153 arcsec/a |
radial velocity | -17 km/s note: variable radial velocity |
|
rotational velocity | 8 km/s (uncertain) (variable) | |
trigonometric parallax | 0,028 arcsec |
note (category: radial and/or rotational velocities): | 1786d, possibly also short period? Rotation 17.492d? |
note (category: dynamical parallaxes): | 0.011". |
magnitude
visual magnitude | 4,69 (V on UBV Johnson system) |
spectral / color information
spectral class | F0IIIp |
B-V-magnitude | 0,26 |
U-B-magnitude | 0,1 |
R-I-magnitude | 0,11 |
note (category: spectra): | Extreme oxygen deficiency. Eu, Cr, Sr strong, DyIII identified. The spectrum has been variously classified as cF1, F0III, and F0pV. Also classified A9Vp(SrCrEu st.,Ca wk.). |
variability information
variable star identification | Gam Equ |
note (category: variability): | ADS 14702A, Alpha CV 4.58 - 4.77V, 314d, 0 00868d. Magnetic field var. 1786d and 72y. Spectrum var. 72y. |
double/multiple star system information
number of components of multiple star system | 4 |
separation | 352,5 arcsec |
mag difference (of double or brightest multiple) | 1,2 |
component ID | AD |
note (category: double and multiple data): | AB binary, B, 11.6v at 2". C, 12.6v at 48" optical. |
miscellaneous information
note (category: group membership): | Wolf 630 group. |
note (category: stellar radii or diameters): | 3 solar radii. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
position (J2000) | RA: 21h 10min 20,518sec | DEC: +10° 7' 53,57'' | ±0,06 arcsec | source: 15 |
proper motion (J2000) | RA: 0,0038 arcsec/a | DEC: -0,153 arcsec/a | source: 25 | |
radial velocity | -17 km/s | source: 25 | ||
trigonometric parallax | 0,028 | ±0,003 arcsec | source: 25 | |
galactic coord. (B1950) | longitude: 59,94° | latitude: -24,76° | ||
GCI unit vector (J2000) | X: 0,726772 | Y: -0,663972 | Z: 0,175909 |
magnitude:
visual | 4,6 (observed) | source: 31 |
photovisual | 4,8 | source: 2 |
spectral information:
spectral class | F0 | source: 96 | |
Morgan-Keenan | F0IIIp | source: 25 | |
B-magnitude | 4,95 ±0,05 | B-V-magnitude | 0,26 |
U-magnitude | 5,05 ±0,05 | U-B-magnitude | 0,1 |
variability information:
variability type | 161 |
var. amplitude | 0,19 |
var. period | 0,01 |
double/multiple star system information:
separation between brightest and second brightest component | 1,4 arcsec |
magnitude difference between brightest and second brightest component | 3,5 |
position angle | 264 ° |
component | magnitude | spectral class | catalogue(s)/name(s) |
A | 4,6 | F0 | g Equulei, 5 Equ, HR 8097, HD 201601, SAO 126593 |
B | 6,07 | A2 | 6 Equ, HR 8098, HD 201616, SAO 126597 |
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 | |
30 | GCVS, 4th edition |
Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88 | |
31 | CRM' (non-GCVS variable data) |
Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 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: 21h 7min 54,579sec | DEC: +9° 55' 44,82'' | ±0,005 arcsec |
position (J2000) | RA: 21h 10min 20,546sec | DEC: +10° 7' 53,33'' | |
proper motion J1950 (FK4) | RA: 0,004 arcsec/a | DEC: -0,152 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
proper motion J2000 (FK5) | RA: 0,0042 arcsec/a | DEC: -0,156 arcsec/a | |
source of proper motion data | Determined by source catalog |
magnitude:
visual | 4,8 (accuracy: 2 decimals) |
source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
spectral class | F0p |
source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
source catalogue | FK4, catalogue number: 1555 |
Durchmusterung | BD+09 4732 |
Boss General Catalogue | 29591 |
Henry Draper Catalogue | 201601 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
position (J2000) | RA: 21h 10,3min | DEC: +10° 8' |
proper motion (J2000) | RA: 0,057 arcsec/a | DEC: -0,153 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 | 1867 | 23 | 276° | 2,1'' | 4,7 | 8,2 | A9V | KNT 5 |
1994 | 264° | 1,4'' | ||||||
AC | 1877 | 10 | 10° | 41,3'' | 4,8 | 12,6 | - | BU 71 |
1925 | 5° | 47,7'' | ||||||
AD | 1835 | 7 | 153° | 366,2'' | 4,8 | 6 | - | STF 54 |
1922 | - | 352,5'' |
discoverer information:
discoverer code | discoverer | reference |
KNT 5 | Knott, G. | - |
BU 71 | Burnham, S.W. | - |
STF 54 | Struve, F.G.W. | - |
notes:
note | Gamma Equ. A is an Alpha CVn-type variable. There apparently is a long-period spectroscopic binary present. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
position (J1950) | RA: 21h 7min 54,6sec | DEC: +9° 55' 45'' |
variability informations:
variability type | ACVO | rotating variable star |
magnitute at max. brightness | 4,58 | |
magnitute at min. brightness | 4,77 | |
photometric system | visual, photovisual or Johnson's V | |
period [d] | 0,00868 |
spectral information
spectral class | F0p(Sr-Cr-Eu) |
references
to a study | Vol. I GCVS (see Kholopov et al. 1985-1988) |
to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
ID in the GCVS catalogue | 35/9003 |
constellation | Equuleus |
notes on existence | The star is equivalent to '0360001 R'. |
There are notes in published catalog. |
variability type description
variability type | description |
ACVO | Alpha2 Canum Venaticorum variables. These are main-sequence stars with spectral types B8p-A7p and displaying strong magnetic fields. Spectra show abnormally strong lines of Si, Sr, Cr, and rare earths whose intensities vary with rotation. They exhibit magnetic field and brightness changes (periods of 0.5-160 days or more). The amplitudes of the brightness changes are usually withine 0.01-0.1 mag in V. ACVO Rapidly oscillating Alpha2 CVn variables. These are nonradially pulsating, rotating magnetic variables of Ap spectral type (DO Eri). Pulsation periods are in the range of 6-12 mmag (0.004-0.01 days), while amplitudes of light variation caused by the pulsation are about 0.01 mag in V. The pulsational variations are superposed on those caused by rotation. |