Caph, a white giant star in Cassiopeia
Caph is a white giant star in the constellation Cassiopeia. At 55 light years away, it is the 75th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 2.28.
Caph (HIP 746)
Caph is a white giant star in the constellation Cassiopeia. At 55 light years away, it is the 75th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 2.28. Caph is the primary component of a multiple-star system and an intrinsic variable star that varies between magntitudes 2.34 and 2.38 over a period of 2.4 hours. The star's age is estimated to be 900 million years but is certainly no less than 800 million years and no greater than 1 billion years. The iron abundance of Caph is +0.03 (107.2% of the Sun). It is moving through the Galaxy at a speed of 44.2 km/s relative to the Sun. Its projected Galactic orbit carries it between 21,800 and 27,000 light years from the center of the Galaxy.
Sky position: RA 0h 9.2m, Dec +59° 9'
Common designations: Caph, Beta Cassiopeiae, 11 Cassiopeiae, HIP 746, HD 432, Gliese 8
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Brightest stars in Cassiopeia:
(list all)
| Rank | Mag. | Star |
| 1 | 2.15 | Gamma Cassiopeiae |
| 2 | 2.24 | Schedar |
3
| 2.28
) Caph
| Rank | Mag. | Star |
| 4 | 2.66 | Ruchbah |
| 5 | 3.35 | Segin |
| 6 | 3.46 | Eta Cassiopeia |
| 7 | 3.69 | Zeta Cassiopeiae |
| 8 | 3.95 | 50 Cassiopeiae |
| 9 | 4.17 | Kappa Cassiopeiae |
| 10 | 4.34 | Marfak |
| 11 | 4.46 | Iota Cassiopeiae |
| 12 | 4.48 | Omicron Cassiopeiae |
| 13 | 4.49 | A Cassiopeiae |
| 14 | 4.51 | Rho Cassiopeiae |
| 15 | 4.62 | Upsilon-2 Cassiopeiae |
| 16 | 4.68 | Chi Cassiopeiae |
| 17 | 4.72 | Psi Cassiopeiae |
Hover over other bright stars to identify or click to jump.
Galactic Orbit of Caph
(compared to the Sun)
E
ccentricity: 10.7% vs. 16.0%Angle φ : -90.7°vs. 26.0°
Semi-major axis : 7,483 pc vs. 8,686 pc
Semi-minor axis: 7,441 pc vs. 8,574 pc
Focus-to-center
: 797 pcvs. 1,388 pcSemilatus rectum : 7,398 pc vs. 8,464 pc
Perigalacticon: 6,686 pc vs. 7,297 pc
Apogalacticon
: 8,280 pcvs. 10,074 pcSome Tabulated XHIP Data for Caph
(see also: SIMBAD)
Astrometry
2007A&A...474..653V
| Position | Proper Motion | |
| Right Ascension: | 2.29204030° ±0.25 mas | 523.50 ±0.32 mas/yr. |
| Declination: | 59.15021806° ±0.26 mas | -179.77 ±0.31 mas/yr. |
| Galactic Longitude: | 117.52688389° | 487.07 mas/yr. |
| Galactic Latitude: | -3.27721799° | -262.94 mas/yr. |
Parallax: 59.58 ± 0.38 mas
Spectrography
Spectral Type: F2III 2003AJ....126.2048G.
Radial Velocity: 4.30 ±0.80 km/s [A rating] 2006AstL...32..759G.
Iron Abundance [Fe/H]:
0.03 dex
2009A&A...501..941H, 2007ApJS..169..430R.
Photometry
| band | magnitude | Abs. Mag. |
| U | ||
| B | 2.66 | 1.54 |
| V | 2.28 | 1.16 |
| R | 2.00 | 0.88 |
| I | 1.90 | 0.78 |
| J | 1.71 | 0.59 |
| H | 1.59 | 0.46 |
| K | 1.45 | 0.33 |
B-V: +0.38 V-I: +0.38
Derivations
Heliocentric distance: 16.78 pc (0.6% margin of error)
Galactocentric distance: 7,408 pc
Transverse velocity: 44.0 km/s
3D heliocentric position and motion:
|
toward: |
Galactic center | Galactic rotation | North Galactic Pole |
| Position ( X, Y, Z) | -7.7 pc | 14.9 pc | -1.0 pc |
| Velocity (U, V, W) | -35.8 km/s | -15.2 km/s | -21.1 km/s |