Theta Aurigae, a blue subgiant star in Auriga
Theta Aurigae is a blue subgiant star in the constellation Auriga. At 165 light years away, it is the 107th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 2.65.
Theta Aurigae (HIP 28380)
Theta Aurigae is a blue subgiant star in the constellation Auriga. At 165 light years away, it is the 107th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 2.65. Theta Aurigae is a multiple-star system and an intrinsic variable star that varies between magntitudes 2.59 and 2.62 over a period of 3.62 days. It is moving through the Galaxy at a speed of 35.8 km/s relative to the Sun. Its projected Galactic orbit carries it between 21,900 and 26,000 light years from the center of the Galaxy. It came closest to the Sun 1.1 million years ago when it had brightened to magnitude 1.45 from a distance of 95 light years.
Sky position: RA 5h 59.7m, Dec +37° 12.6'
Common designations: Theta Aurigae, 37 Aurigae, HIP 28380, HD 40312
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Brightest stars in Auriga:
(list all)
| Rank | Mag. | Star |
| 1 | 0.08 | Capella |
| 2 | 1.90 | Menkalinan |
3
| 2.65
) Theta Aurigae
| Rank | Mag. | Star |
| 4 | 2.69 | Hassaleh |
| 5 | 3.03 | Al Anz |
| 6 | 3.18 | Hoedus II |
| 7 | 3.69 | Hoedus I |
| 8 | 3.72 | Delta Aurigae |
| 9 | 3.97 | Nu Aurigae |
| 10 | 4.30 | Pi Aurigae |
| 11 | 4.32 | Kappa Aurigae |
| 12 | 4.51 | Tau Aurigae |
| 13 | 4.54 | 16 Aurigae |
| 14 | 4.69 | Lambda Aurigae |
| 15 | 4.71 | Chi Aurigae |
| 16 | 4.72 | Upsilon Aurigae |
| 17 | 4.79 | 2 Aurigae |
Hover over other bright stars to identify or click to jump.
Galactic Orbit of Theta Aurigae
(compared to the Sun)
E
ccentricity: 8.4% vs. 16.0%Angle φ : -104.3°vs. 26.0°
Semi-major axis : 7,347 pc vs. 8,686 pc
Semi-minor axis: 7,321 pc vs. 8,574 pc
Focus-to-center
: 618 pcvs. 1,388 pcSemilatus rectum : 7,295 pc vs. 8,464 pc
Perigalacticon: 6,729 pc vs. 7,297 pc
Apogalacticon
: 7,966 pcvs. 10,074 pcSome Tabulated XHIP Data for Theta Aurigae
(see also: SIMBAD)
Astrometry
2007A&A...474..653V
| Position | Proper Motion | |
| Right Ascension: | 89.93015902° ±0.15 mas | 43.63 ±0.21 mas/yr. |
| Declination: | 37.21276398° ±0.08 mas | -73.79 ±0.08 mas/yr. |
| Galactic Longitude: | 174.33817457° | 85.70 mas/yr. |
| Galactic Latitude: | 6.72932425° | 2.18 mas/yr. |
Parallax: 19.70 ± 0.16 mas
Spectrography
Spectral Type: B9IV 2009A&A...501..297Z.
Radial Velocity: 29.30 ±1.70 km/s [A rating] 2006AstL...32..759G.
Iron Abundance [Fe/H]:
n/a
Photometry
band
magnitude
Abs. Mag.
U
B
2.57
-0.96
V
2.65
-0.88
R
I
2.70
-0.83
J
H
K
B-V: -0.08 V-I: -0.05
Derivations
Heliocentric distance: 50.76 pc (0.8% margin of error)
Galactocentric distance: 7,450 pc
Transverse velocity: 20.6 km/s
3D heliocentric position and motion:
|
toward: |
Galactic center | Galactic rotation | North Galactic Pole |
| Position ( X, Y, Z) | -50.2 pc | 5.0 pc | 5.9 pc |
| Velocity (U, V, W) | -30.9 km/s | -17.7 km/s | 4.0 km/s |