Altair
catalogues and names
| catalogues and names | Altair, a Aql, NSV 24910, 53 Aql, HR 7557, HD 187642, SAO 125122, BD +8 4236, FK5: 745, WDS 19508+0852A |
| other names | Atair |
| constellation | Aquila |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | ALTAIR; Atair. |
position, motion, parallax:
| position (J2000) | RA: 19h 50min 47sec | DEC: +8° 52' 6'' | ||
| position (B1900) | RA: 19h 45min 54.2sec | DEC: +8° 36' 15'' | ||
| proper motion (J2000) | RA: 0.538 arcsec/a | DEC: 0.386 arcsec/a | ||
| radial velocity | -26 km/s | |||
| rotational velocity | 242 km/s (uncertain) (variable) | |||
| trigonometric parallax | 0.198 arcsec | |||
| galactic coordinates | longitude: 47.74° | latitude: -8.91° | ||
magnitude
| visual magnitude | 0.77 (V on UBV Johnson system) |
spectral / color information
| spectral class | A7V |
| B-V-magnitude | 0.22 |
| U-B-magnitude | 0.08 |
| R-I-magnitude | |
| IR-note | object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978) |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 165.2 arcsec |
| mag difference (of double or brightest multiple) | 8.6 |
| component ID | AB |
| note (category: double and multiple data): | Component B optical. |
miscellaneous information
| note (category: stellar radii or diameters): | Diam. = 0.00278 - 0.00298". |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 19h 50min 47.002sec | DEC: +8° 52' 6.03'' | ±0.06 arcsec | source: 15 |
| proper motion (J2000) | RA: 0.0363 arcsec/a | DEC: 0.386 arcsec/a | source: 25 | |
| radial velocity | -26 km/s | source: 25 | ||
| trigonometric parallax | 0.198 arcsec | ±0.02 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 47.74° | latitude: -8.91° | ||
magnitude:
| visual | 0.77 (observed) | source: 25 |
| photovisual | 0.9 | source: 2 |
spectral information:
| spectral class | A5 | source: 96 | |
| Morgan-Keenan | A7V | source: 25 | |
| B-magnitude | 0.99 ±0.05 | B-V-magnitude | 0.22 |
| U-magnitude | 1.07 ±0.05 | U-B-magnitude | 0.08 |
double/multiple star system information:
| separation between brightest and second brightest component | 165.2 arcsec |
| magnitude difference between brightest and second brightest component | 8.8 |
| position angle | 301 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 0.77 | A5 | Altair, a Aquilae, 53 Aql, HR 7557, HD 187642, SAO 125122 |
| B | 9.6 | - |
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 (B1950) | RA: 19h 48min 20.59sec | DEC: +8° 44' 5.71'' | ±0.003 arcsec |
| position (J2000) | RA: 19h 50min 47.001sec | DEC: +8° 52' 6.07'' | |
| proper motion B1950 (FK4) | RA: 0.0362 arcsec/a | DEC: 0.387 arcsec/a | ±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0363 arcsec/a | DEC: 0.387 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 0.9 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | A5 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 745 |
| Durchmusterung | BD+08 4236 |
| Boss General Catalogue | 27470 |
| Henry Draper Catalogue | 187642 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 19h 50.8min | DEC: +8° 52' |
| proper motion (J2000) | RA: 0.538 arcsec/a | DEC: 0.386 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 | 1836 | 13 | 322° | 152.4'' | 0.77 | 9.6 | A7V | STF 10 |
| 1925 | 301° | 165.2'' | ||||||
| AC | 1905 | 2 | 94° | 238.4'' | 0.77 | 10.1 | - | STF 10 |
| 1959 | 100° | 247.2'' |
discoverer information:
| discoverer code | discoverer | reference |
| STF 10 | Struve, F.G.W. | - |
notes:
| note | Alpha Aql. B is BD+08@4232. Proper motion of B +003 -009. |