Achird
catalogues and names | Achird, h Cas, eta Cas, 24 Cas, HR 219, HD 4614, SAO 21732, WDS 00491+5749A |
other names | according to Becvar |
constellation | Cassiopeia |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
note (category: star names): | Achird, according to Becvar; Allen says "unnamed". |
position, motion, parallax:
position (J2000) | RA: 0h 49min 6sec | DEC: +57° 48' 57'' |
position (J1900) | RA: 0h 43min 3sec | DEC: +57° 17' 6'' |
proper motion (J2000) | RA: 1,1 arcsec/a | DEC: -0,529 arcsec/a |
radial velocity | 9 km/s note: spectroscopic binaries, single lined spectra note: orbital data avaible |
|
rotational velocity | =<6 km/s (uncertain) (variable) | |
trigonometric parallax | 0,176 arcsec |
note (category: radial and/or rotational velocities): | Component B, +11k/s. |
note (category: dynamical parallaxes): | 0.177". |
magnitude
visual magnitude | 3,44 (V on UBV Johnson system) |
spectral / color information
spectral class | F9V+dM0 |
B-V-magnitude | 0,57 |
U-B-magnitude | 0,01 |
R-I-magnitude | 0,36 |
double/multiple star system information
number of components of multiple star system | 8 |
separation | 11,6 arcsec |
mag difference (of double or brightest multiple) | 4 |
component ID | AB |
note (category: double and multiple data): | AB 3.45 G3V, 7.51 K4Ve, 480y, a = 11.994". Combined mag., colors. Component B, vsini =<25k/s. Companions C-H optical. A possible invisible companion with period about 40y. Component B, 7.51V, +1.39(B-V), +1.03(U-B). |
note (category: spectroscopic binaries): | ADS 671A, 9.209d, K 2.2k/s, V0 +9.2k/s, asini 0.254. More recent observations by Morbey and Griffin (1987) and by McMillan and Smith (1988) show constant velocity; thus, the SB nature of the system is questioned. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
position (J2000) | RA: 0h 49min 6,521sec | DEC: +57° 48' 56,4'' | ±0,43 arcsec | source: 16 |
proper motion (J2000) | RA: 0,1421 arcsec/a | DEC: -0,537 arcsec/a | source: 25 | |
radial velocity | 9 km/s | source: 25 | ||
trigonometric parallax | 0,176 | ±0,018 arcsec | source: 25 | |
galactic coord. (B1950) | longitude: 122,61° | latitude: -5,05° | ||
GCI unit vector (J2000) | X: 0,520464 | Y: 0,113262 | Z: 0,846339 |
magnitude:
visual | 3,44 (observed) | source: 25 |
photovisual | 3,6 | source: 2 |
photographic | 4,1 | source: 16 |
spectral information:
spectral class | F8 | source: 96 | |
Morgan-Keenan | F9V+M0-V | source: 25 | |
B-magnitude | 4,01 ±0,05 | B-V-magnitude | 0,57 |
U-magnitude | 4,02 ±0,05 | U-B-magnitude | 0,01 |
double/multiple star system information:
separation between brightest and second brightest component | 12,2 arcsec |
magnitude difference between brightest and second brightest component | 4,07 |
position angle | 315 ° |
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 | |
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: 0h 46min 3,645sec | DEC: +57° 33' 3,15'' | ±0,012 arcsec |
position (J2000) | RA: 0h 49min 6,04sec | DEC: +57° 48' 57,21'' | |
proper motion J1950 (FK4) | RA: 0,1368 arcsec/a | DEC: -0,521 arcsec/a | ±0,002 arcsec/a in RA ±0,002 arcsec/a in DEC |
proper motion J2000 (FK5) | RA: 0,1377 arcsec/a | DEC: -0,529 arcsec/a | |
source of proper motion data | Determined by source catalog |
magnitude:
visual | 3,6 (accuracy: 2 decimals) |
source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
spectral class | F8 |
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: 962 |
Durchmusterung | BD+57 150 |
Boss General Catalogue | 962 |
Henry Draper Catalogue | 4614 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
position (J2000) | RA: 0h 49,1min | DEC: +57° 49' |
proper motion (J2000) | RA: 0 arcsec/a | DEC: -0,572 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 | 1820 | often | 81° | 10,7'' | 3,44 | 7,51 | G0V dM0 | STF 60 |
1993 | 315° | 12,2'' | ||||||
AC | 1912 | 2 | 234° | 154,5'' | 3,44 | 11,4 | - | STF 60 |
1922 | 238° | 158,9'' | ||||||
AD | 1912 | 2 | 34° | 159,8'' | 3,6 | 11,6 | - | STF 60 |
1921 | 30° | 159,6'' | ||||||
AE | 1912 | 7 | 120° | 203,2'' | 3,6 | 9 | - | STF 60 |
1931 | - | 190,6'' | ||||||
AF | 1913 | 1 | 268° | 281,7'' | 3,6 | - | - | STF 60 |
AG | 1913 | 4 | 243° | 338,5'' | 3,6 | 8,9 | - | STF 60 |
1915 | - | 339,2'' | ||||||
BC | 1913 | 1 | 118° | 209,1'' | - | - | - | STF 60 |
BH | 1928 | 1 | 2° | 10,8'' | 7,2 | 8,6 | - | STF 60 |
discoverer information:
discoverer code | discoverer | reference |
STF 60 | Struve, F.G.W. | - |
notes:
note | Eta Cas. Proper motion of A +1141 -572. P = 480yr., a = 12.0", motion direct. A has been reported to be a spectroscopic binary, but this is not confirmed. |