Omicron Aquilae
 Location of ο Aquilae (circled) |
|
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Aquila |
| Right ascension | 19h 51m 01.64400s[1] |
| Declination | +10° 24′ 56.5992″[1] |
| Apparent magnitude (V) | 5.11[2] |
| Characteristics | |
| Spectral type | F8 V + M3 V[3] |
| U−B color index | 0.07 |
| B−V color index | 0.55[4] |
| R−I color index | 0.29 |
| Astrometry | |
| Radial velocity (Rv) | –0.2[5] km/s |
| Proper motion (μ) | RA: +242.28[1] mas/yr Dec.: –136.48[1] mas/yr |
| Parallax (π) | 52.11 ± 0.29[1] mas |
| Distance | 62.6 ± 0.3 ly (19.2 ± 0.1 pc) |
| Absolute magnitude (MV) | 3.71[5] |
| Details | |
| ο Aql A | |
| Mass | 1.252[6] M☉ |
| Radius | 1.52[6] R☉ |
| Surface gravity (log g) | 4.07[7] cgs |
| Temperature | 6,090[7] K |
| Metallicity [Fe/H] | +0.07[7] dex |
| Rotational velocity (v sin i) | 3[4] km/s |
| Age | 3.3[5] Gyr |
| ο Aql C | |
| Mass | 0.33[8] M☉ |
| Other designations | |
| Data sources: | |
| Hipparcos Catalogue, CCDM (2002), Bright Star Catalogue (5th rev. ed.) |
|
Omicron Aquilae (ο Aql, ο Aquilae) is the Bayer designation for a double star in the equatorial constellation of Aquila. The brighter component has an apparent visual magnitude of +5.11,[2] which means it is faintly visible to the naked eye in dark suburban skies. The annual parallax shift of this star is 52.11 mas,[1] which is equivalent to a physical distance of 62.6 light-years (19.2 parsecs) from Earth.
The primary component, Omicron Aquilae A, is an F-type main sequence star with a stellar classification of F8 V.[3] It has about 125% of the mass of the Sun and 152% of the Sun's radius.[6] With an age of roughly 3.3 billion years,[5] it appears to spinning at a leisurely rate with a projected rotational velocity of 3 km/s.[4] The outer atmosphere has an effective temperature of 6,090 K,[7] giving it the yellowish-white hue of an F-type star.
In 1998, Omicron Aquilae was one of nine stars identified as experiencing a superflare. The first flare observed from Omicron Aquilae was in 1979, with a magnitude increase of 0.07 and a duration of less than five days. The second occurred in 1980, with a magnitude change of 0.09 and a duration of fifteen days. The energy released during the second flare is estimated as 9 × 1037 erg.[10]
There is a magnitude 12.67 common proper motion companion located at an angular separation of 22.5 arcseconds along a position angle of 221°. Based upon its matching parallax value, this corresponds to a projected linear separation of 431 astronomical units. (Hence, the companion is located at this separation or greater.) Designated component C, this is a small red dwarf star with a stellar classification of M3 V. Component B is an optical companion that appears near the primary only through a chance alignment.[3]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 3.0 3.1 3.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 4.0 4.1 4.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 5.0 5.1 5.2 5.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 6.0 6.1 6.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 7.0 7.1 7.2 7.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
