HD 194244

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.

HD 194244

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
BD+00° 4495, HD 194244, HIP 100664, HR 7803, SAO 125769.
Database references
SIMBAD	data

References

1. 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
2. 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
3. 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
4. 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.
5. 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
6. 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
7. 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

• HR 7803
• Image HD 194244