HD 194244
(Redirected from HR 7803)
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 20h 24m 37.49846s[1] |
| Declination | +01° 04′ 06.2592″[1] |
| Apparent magnitude (V) | 6.14[2] |
| Characteristics | |
| Spectral type | B9V[3] |
| U−B color index | −0.14[2] |
| B−V color index | −0.04[2] |
| Astrometry | |
| Radial velocity (Rv) | −9.6±0.9[4] km/s |
| Proper motion (μ) | RA: +8.37[1] mas/yr Dec.: +5.26[1] mas/yr |
| Parallax (π) | 4.04 ± 0.39 mas[1] |
| Distance | 810 ± 80 ly (250 ± 20 pc) |
| Details | |
| Luminosity | 173[5] L☉ |
| Temperature | 8,822[5] K |
| Rotational velocity (v sin i) | 222[6] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 194244 is a variable Be star[7] in the equatorial constellation of Aquila. With an apparent magnitude of 6.14, according to the Bortle scale it is faintly visible to the naked eye from rural skies on a dark night.
References
[edit]- ^ a b c d e van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600Vizier catalog entry
- ^ a b c Cousins, A. W. J. (1964), "Photometric Data for Stars in the Equatorial Zone (Seventh List)", Monthly Notes of the Astronomical Society of Southern Africa, 23: 175, Bibcode:1964MNSSA..23..175C
- ^ Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819
- ^ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
- ^ a b McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352
- ^ Royer, F.; Zorec, J.; Gómez, A. E. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298
- ^ Neiner, C.; Hubert, A.-M.; Catala, C. (February 2005), "The Identification of New Be Stars in GAUDI", The Astrophysical Journal Supplement Series, 156 (2): 237–243, Bibcode:2005ApJS..156..237N, doi:10.1086/426670
External links
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