Omicron-2 Cygni, an orange supergiant star in Cygnus
Omicron-2 Cygni is an orange supergiant star in the constellation Cygnus. At 1,040 light years away, it is the 498th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 3.96.
Omicron-2 Cygni (HIP 99848)
Omicron-2 Cygni is an orange supergiant star in the constellation Cygnus. At 1,040 light years away, it is the 498th brightest star in the Earth's sky, where it shines at an apparent visual magnitude of 3.96. Omicron-2 Cygni is the primary component of a multiple-star system. The iron abundance of Omicron-2 Cygni is -0.33 (46.8% of the Sun). It is moving through the Galaxy at a speed of 10.2 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,000 and 28,000 light years from the center of the Galaxy.
Sky position: RA 20h 15.5m, Dec +47° 42.6'
Common designations: Omicron-2 Cygni, 32 Cygni, HIP 99848, HD 192909, HR 7751
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Brightest stars in Cygnus:
(list all)
| Rank | Mag. | Star |
| 5 | 3.05 | Albireo A |
| 6 | 3.21 | Zeta Cygni |
| 7 | 3.72 | Xi Cygni |
| 8 | 3.74 | Tau Cygni |
| 9 | 3.76 | Iota Cygni |
| 10 | 3.80 | Kappa Cygni |
| 11 | 3.80 | Omicron-1 Cygni |
| 12 | 3.89 | Eta Cygni |
| 13 | 3.94 | Nu Cygni |
14
| 3.96
) Omicron-2 Cygni
| Rank | Mag. | Star |
| 15 | 3.98 | Rho Cygni |
| 16 | 4.01 | 41 Cygni |
| 17 | 4.22 | 52 Cygni |
| 18 | 4.22 | Sigma Cygni |
| 19 | 4.23 | Pi-2 Cygni |
| 20 | 4.28 | 33 Cygni |
| 21 | 4.41 | Upsilon Cygni |
Hover over other bright stars to identify or click to jump.
Galactic Orbit of Omicron-2 Cygni
(compared to the Sun)
E
ccentricity: 7.8% vs. 16.0%Angle φ : -12.9°vs. 26.0°
Semi-major axis : 7,981 pc vs. 8,686 pc
Semi-minor axis: 7,957 pc vs. 8,574 pc
Focus-to-center
: 623 pcvs. 1,388 pcSemilatus rectum : 7,933 pc vs. 8,464 pc
Perigalacticon: 7,359 pc vs. 7,297 pc
Apogalacticon
: 8,604 pcvs. 10,074 pcSome Tabulated XHIP Data for Omicron-2 Cygni
(see also: SIMBAD)
Astrometry
2007A&A...474..653V
| Position | Proper Motion | |
| Right Ascension: | 303.86799288° ±0.29 mas | 1.80 ±1.40 mas/yr. |
| Declination: | 47.71420571° ±0.30 mas | 4.50 ±1.40 mas/yr. |
| Galactic Longitude: | 83.66875845° | 4.75 mas/yr. |
| Galactic Latitude: | 7.04555856° | 0.95 mas/yr. |
Parallax: 3.08 ± 0.37 mas
Spectrography
Spectral Type: K7Ib-II + B1V 2000ApJ...541..298W.
Radial Velocity:
-7.13 ±1.59 km/s [A rating]
2005A&A...430..165F.
This star is a spectroscopic binary with a solved orbit.
Iron Abundance [Fe/H]:
-0.33 dex
1990ApJS...74.1075M.
Photometry
| band | magnitude | Abs. Mag. |
| U | ||
| B | 5.41 | -2.11 |
| V | 3.96 | -3.56 |
| R | ||
| I | 2.72 | -4.80 |
| J | ||
| H | ||
| K |
B-V: +1.45 V-I: +1.24
Derivations
Heliocentric distance: 319.15 pc (12.0% margin of error)
Galactocentric distance: 7,372 pc
Transverse velocity: 7.3 km/s
3D heliocentric position and motion:
|
toward: |
Galactic center | Galactic rotation | North Galactic Pole |
| Position ( X, Y, Z) | 34.9 pc | 314.8 pc | 39.1 pc |
| Velocity (U, V, W) | -7.9 km/s | -6.4 km/s | 0.6 km/s |