Pollux, a yellow giant star in Gemini
Pollux is a yellow giant star in the constellation Gemini. At 34 light years away, it is the 17th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 1.16.
Pollux (HIP 37826)
Pollux is a yellow giant star in the constellation Gemini. At 34 light years away, it is the 17th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 1.16. Pollux is the primary component of a multiple-star system. The iron abundance of Pollux is +0.08 (120.2% of the Sun). It is moving through the Galaxy at a speed of 31 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,100 and 36,400 light years from the center of the Galaxy. Pollux has one confirmed planet know to date (early 2012).
Sky position: RA 7h 45.3m, Dec +28° 1.8'
Common designations: Pollux, Beta Geminorum, 78 Geminorum, HIP 37826, HD 62509, Gliese 286
Learn how to find naked-eye stars with:
Stars of the Northern Hemisphere
Deluxe Astronomy Poster
Brightest stars in Gemini:
(list all)
1
| 1.16
) Pollux
| Rank | Mag. | Star |
| 2 | 1.58 | Castor |
| 3 | 1.93 | Alhena |
| 4 | 2.87 | Tejat Posterior |
| 5 | 3.06 | Mebsuta |
| 6 | 3.31 | Tejat Prior |
| 7 | 3.35 | Alzirr |
| 8 | 3.50 | Wasat |
| 9 | 3.57 | Kappa Geminorum |
| 10 | 3.58 | Lambda Geminorum |
| 11 | 3.60 | Theta Geminorum |
| 12 | 3.78 | Propus |
| 13 | 4.01 | Mekbuda |
| 14 | 4.06 | Upsilon Geminorum |
| 15 | 4.13 | Nu Geminorum |
| 16 | 4.16 | Propus |
| 17 | 4.16 | Rho Geminorum |
Hover over other bright stars to identify or click to jump.
Galactic Orbit of Pollux
(compared to the Sun)
E
ccentricity: 20.2% vs. 16.0%Angle φ : -3.4°vs. 26.0°
Semi-major axis : 9,280 pc vs. 8,686 pc
Semi-minor axis: 9,089 pc vs. 8,574 pc
Focus-to-center
: 1,873 pcvs. 1,388 pcSemilatus rectum : 8,902 pc vs. 8,464 pc
Perigalacticon: 7,407 pc vs. 7,297 pc
Apogalacticon
: 11,152 pcvs. 10,074 pcSome Tabulated XHIP Data for Pollux
(see also: SIMBAD)
Astrometry
2007A&A...474..653V
| Position | Proper Motion | |
| Right Ascension: | 116.33068294° ±0.25 mas | -626.55 ±0.30 mas/yr. |
| Declination: | 28.02631022° ±0.14 mas | -45.80 ±0.18 mas/yr. |
| Galactic Longitude: | 192.22971814° | -165.10 mas/yr. |
| Galactic Latitude: | 23.40773954° | -606.14 mas/yr. |
Parallax: 96.54 ± 0.27 mas
Spectrography
Spectral Type: G9III 2008ApJS..176..216A.
Radial Velocity: 3.23 ±0.02 km/s [A rating] 2005A&A...430..165F.
Iron Abundance [Fe/H]:
0.08 dex
2011A&A...525A..71W, 2008A&A...480...91S, 2007A&A...475.1003H, 2007A&A...465..271R, 2005AJ....129.1063L, 2004A&A...420..183A, 1998A&A...338..623M, 1990ApJS...74.1075M, 1981ApJ...248..228L.
Photometry
| band | magnitude | Abs. Mag. |
| U | ||
| B | 2.15 | 2.07 |
| V | 1.16 | 1.08 |
| R | 0.60 | 0.52 |
| I | 0.20 | 0.12 |
| J | -0.32 | -0.39 |
| H | -0.85 | -0.92 |
| K | -0.94 | -1.01 |
B-V: +0.99 V-I: +0.96
Derivations
Heliocentric distance: 10.36 pc (0.3% margin of error)
Galactocentric distance: 7,409 pc
Transverse velocity: 30.8 km/s
3D heliocentric position and motion:
|
toward: |
Galactic center | Galactic rotation | North Galactic Pole |
| Position ( X, Y, Z) | -9.3 pc | -2.0 pc | 4.1 pc |
| Velocity (U, V, W) | -16.2 km/s | 4.8 km/s | -26.0 km/s |