Alcor
| catalogues and names | Alcor, NSV 06238, 80 UMa, HR 5062, HD 116842, SAO 28751 |
| other names | Saidak |
| constellation | Ursa Major |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | ALCOR; Saidak. |
position, motion, parallax:
| position (J2000) | RA: 13h 25min 13,5sec | DEC: +54° 59' 17'' |
| position (J1900) | RA: 13h 21min 13,1sec | DEC: +55° 30' 32'' |
| proper motion (J2000) | RA: 0,118 arcsec/a | DEC: -0,016 arcsec/a |
| radial velocity | -9 km/s note: spectroscopic binaries |
|
| rotational velocity | 218 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,045 arcsec | |
magnitude
| visual magnitude | 4,01 (V on UBV Johnson system) |
spectral / color information
| spectral class | A5V |
| B-V-magnitude | 0,16 |
| U-B-magnitude | 0,08 |
| R-I-magnitude | 0,07 |
variability information
| variable star identification | 6238 |
| note (category: variability): | Delta Sct. |
double/multiple star system information
| note (category: double and multiple data): | CPM with HR 5054-5. |
miscellaneous information
| note (category: group membership): | "Dipper Stars;" Sirius group; UMa stream; UMa moving cluster. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 13h 25min 13,541sec | DEC: +54° 59' 16,56'' | ±0,35 arcsec | source: 17 |
| proper motion (J2000) | RA: 0,0139 arcsec/a | DEC: -0,023 arcsec/a | source: 25 | |
| radial velocity | -9 km/s | source: 25 | ||
| trigonometric parallax | 0,045 | ±0,004 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 112,76° | latitude: 61,47° | ||
| GCI unit vector (J2000) | X: -0,534533 | Y: -0,208475 | Z: 0,819031 | |
magnitude:
| visual | 4,01 (observed) | source: 25 |
| photovisual | 4 | source: 2 |
| photographic | 4,2 | source: 16 |
spectral information:
| spectral class | A5 | source: 96 | |
| Morgan-Keenan | A5V | source: 25 | |
| B-magnitude | 4,17 ±0,05 | B-V-magnitude | 0,16 |
| U-magnitude | 4,25 ±0,05 | U-B-magnitude | 0,08 |
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 | |
| 17 | ACRS |
| Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 1991 | |
| 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: 13h 23min 13,477sec | DEC: +55° 14' 52,99'' | ±0,012 arcsec |
| position (J2000) | RA: 13h 25min 13,498sec | DEC: +54° 59' 17,15'' | |
| proper motion J1950 (FK4) | RA: 0,0134 arcsec/a | DEC: -0,021 arcsec/a | ±0,002 arcsec/a in RA ±0,002 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0,0138 arcsec/a | DEC: -0,016 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 4 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | A5 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | GC, catalogue number: 18155 |
| Durchmusterung | BD+55 1603 |
| Boss General Catalogue | 18155 |
| Henry Draper Catalogue | 116842 |
data from Combined General Catalogue of Variable Stars (suspected variables) (Kholopov+ 1998)
position:
| position (J1950) | RA: 13h 23min 13,1sec | DEC: +55° 14' 53'' |
variability informations:
| magnitute at max. brightness | 3,95 |
| magnitute at min. brightness | 4,03 |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | A5 |
references
| to a study | 142468D (designation: ALCOR) |
miscanellous
| There are notes in the published catalog (Kukarkin et al.(1982)). |