Pi Aquilae
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila[1] |
| Right ascension | 19h 48m 42.059s[2] |
| Declination | +11° 48′ 57.22″[2] |
| Apparent magnitude (V) | 5.85 (6.47 + 6.75)[3] |
| Characteristics | |
| Spectral type | G8 III: + A1 V[3][4] |
| Astrometry | |
| π Aql A | |
| Radial velocity (Rv) | +12.6[4] km/s |
| Proper motion (μ) | RA: +17.838 mas/yr[2] Dec.: −9.891 mas/yr[2] |
| Parallax (π) | 6.3883±0.0342 mas[2] |
| Distance | 511 ± 3 ly (156.5 ± 0.8 pc) |
| Absolute magnitude (MV) | −0.22[1] |
| Details | |
| π Aql A | |
| Luminosity | 108[1] L☉ |
| Temperature | 5,937+1,255 −569[5] K |
| π Aql B | |
| Radius | 10.9+0.5 −0.9[6] R☉ |
| Luminosity | 74.3±0.9[6] L☉ |
| Surface gravity (log g) | 4.5[6] cgs |
| Temperature | 5,128+226 −105[6] K |
| Other designations | |
| π Aql, 52 Aquilae, BD+11 3994, HIP 97473, HR 7544, SAO 105282, WDS J19487+1149A[7] | |
| A: HD 187259 | |
| B: HD 187260 | |
| Database references | |
| SIMBAD | data |
| A | |
| B | |
Pi Aquilae is a binary star[3] system in the equatorial constellation of Aquila, about 3° to the north of the bright star Altair.[4] Its name is a Bayer designation that is Latinised from π Aquilae, and abbreviated Pi Aql or π Aql. The apparent visual magnitude of the system is 5.85,[3] making it faintly visible to the naked eye from dark suburban skies. Based upon an annual parallax shift of 6.39 mas, the distance to this system is approximately 511 light-years (157 parsecs).[2]
The binary nature of this system was first discovered by William Herschel in 1785.[4] The primary component is a magnitude 6.47[3] giant star with a stellar classification of G8 III:.[3] A companion star at an angular separation of 1.437 arcseconds is an A-type main-sequence star with a classification of A1 V.[3] It is slightly fainter, with an apparent magnitude of 6.75.[3]
References
[edit]- ^ a b c Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e f g h Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ a b c d Griffin, R. (December 1989), "Composite Spectra - Part Three - Pi-Aquilae", Journal for the History of Astronomy, 10 (4): 433, Bibcode:1989JApA...10..433G, doi:10.1007/BF02715077, S2CID 124841724.
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ "* pi. Aql". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-20.
