Pi-2 Orionis, a white main-sequence star in Orion
Pi-2 Orionis is a white main-sequence star in the constellation Orion. At 224 light years away, it shines at an apparent visual magnitude of 4.35.
Pi-2 Orionis (HIP 22509)
Pi-2 Orionis is a white main-sequence star in the constellation Orion. At 224 light years away, it shines at an apparent visual magnitude of 4.35. The iron abundance of Pi-2 Orionis is -0.2 (63.1% of the Sun). It is moving through the Galaxy at a speed of 26.3 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,200 and 26,400 light years from the center of the Galaxy. It came closest to the Sun 2.4 million years ago when it had brightened to magnitude 2.21 from a distance of 84 light years.
Sky position: RA 4h 50.6m, Dec +8° 54'
Common designations: Pi-2 Orionis, 2 Orionis, HIP 22509, HD 30739
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Brightest stars in Orion:
(list all)
| Rank | Mag. | Star |
| 12 | 3.59 | Tau Orionis |
| 13 | 3.68 | Pi-4 Orionis |
| 14 | 3.71 | Pi-5 Orionis |
| 15 | 3.77 | Sigma Orionis |
| 16 | 4.06 | Omicron-2 Orionis |
| 17 | 4.09 | Phi-2 Orionis |
| 18 | 4.12 | Mu Orionis |
| 19 | 4.13 | 29 Orionis |
| 20 | 4.20 | A Orionis |
21
| 4.35
) Pi-2 Orionis
| Rank | Mag. | Star |
| 22 | 4.39 | Phi-1 Orionis |
| 23 | 4.39 | Chi-1 Orionis |
| 24 | 4.42 | Nu Orionis |
| 25 | 4.45 | Xi Orionis |
| 26 | 4.46 | Rho Orionis |
| 27 | 4.47 | Pi-6 Orionis |
| 28 | 4.50 | Omega Orionis |
Hover over other bright stars to identify or click to jump.
Galactic Orbit of Pi-2 Orionis
(compared to the Sun)
E
ccentricity: 4.4% vs. 16.0%Angle φ : -33.3°vs. 26.0°
Semi-major axis : 7,749 pc vs. 8,686 pc
Semi-minor axis: 7,742 pc vs. 8,574 pc
Focus-to-center
: 337 pcvs. 1,388 pcSemilatus rectum : 7,734 pc vs. 8,464 pc
Perigalacticon: 7,412 pc vs. 7,297 pc
Apogalacticon
: 8,086 pcvs. 10,074 pcSome Tabulated XHIP Data for Pi-2 Orionis
(see also: SIMBAD)
Astrometry
2007A&A...474..653V
| Position | Proper Motion | |
| Right Ascension: | 72.65300896° ±0.29 mas | 1.08 ±0.43 mas/yr. |
| Declination: | 8.90025307° ±0.24 mas | -30.05 ±0.35 mas/yr. |
| Galactic Longitude: | 189.82262739° | 25.51 mas/yr. |
| Galactic Latitude: | -21.82850486° | -15.93 mas/yr. |
Parallax: 14.53 ± 0.38 mas
Spectrography
Spectral Type: A0Vnp lambda Boo 1995ApJS...99..135A.
Radial Velocity: 24.40 ±2.60 km/s [A rating] 2006AstL...32..759G.
Iron Abundance [Fe/H]:
-0.20 ±0.04 dex
2011A&A...525A..71W.
Photometry
| band | magnitude | Abs. Mag. |
| U | ||
| B | 4.36 | 0.17 |
| V | 4.35 | 0.16 |
| R | ||
| I | 4.32 | 0.13 |
| J | 3.83 | -0.36 |
| H | 4.21 | 0.02 |
| K | 4.17 | -0.02 |
B-V: +0.01 V-I: +0.03
Derivations
Heliocentric distance: 68.77 pc (2.6% margin of error)
Galactocentric distance: 7,463 pc
Transverse velocity: 9.8 km/s
3D heliocentric position and motion:
|
toward: |
Galactic center | Galactic rotation | North Galactic Pole |
| Position ( X, Y, Z) | -62.9 pc | -10.9 pc | -25.6 pc |
| Velocity (U, V, W) | -19.0 km/s | -11.7 km/s | -13.9 km/s |