HD 194244

HD 194244

Observation data Epoch J2000       Equinox J2000
Constellation	Aquila [1]
Right ascension	20h 24m 37.49817s [2]
Declination	+01° 04′ 06.2574″ [2]
Apparent magnitude  (V)	6.14 [3]
Characteristics
Evolutionary stage	main sequence [4]
Spectral type	B9V [5]
U−B color index	−0.14 [3]
B−V color index	−0.04 [3]
Astrometry
Radial velocity (Rv)	−9.6±0.9 [6] km/s
Proper motion (μ)	RA: +7.834 [2] mas/yr Dec.: +4.935 [2] mas/yr
Parallax (π)	4.0349±0.0.428  mas [2]
Distance	808 ± 0  ly (248 ± 0  pc)
Absolute magnitude  (MV)	−0.80 [1]
Details
Mass	2.5 [7]   M☉
Radius	4.9 [7]   R☉
Luminosity	238 [7]   L☉
Surface gravity (log g)	3.48 [7]   cgs
Temperature	10,233 [7]   K
Metallicity [Fe/H]	−0.22 [8]   dex
Rotation	27.15 [9]
Rotational velocity (v sin i)	222 [4]  km/s
Age	243 [10]   Myr
Other designations
BD+00°4495, HD 194244, HIP 100664, HR 7803, SAO 125769
Database references
SIMBAD	data

HD 194244 is a variable Be star ^[11] 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

1. 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
2. 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.
3. 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
4. Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics, 537: A120, arXiv: 1201.2052 , Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691
5. 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
6. 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
7. Stassun, Keivan G.; et al. (2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv: 1905.10694 . Bibcode:2019AJ....158..138S. doi: 10.3847/1538-3881/ab3467 .
8. Katz, D.; Soubiran, C.; Cayrel, R.; Barbuy, B.; Friel, E.; Bienaymé, O.; Perrin, M. -N. (2011), "Probing the Galactic thick disc vertical properties and interfaces", Astronomy and Astrophysics, 525: A90, Bibcode:2011A&A...525A..90K, doi:10.1051/0004-6361/201014840
9. Oelkers, Ryan J.; Rodriguez, Joseph E.; Stassun, Keivan G.; Pepper, Joshua; Somers, Garrett; Kafka, Stella; Stevens, Daniel J.; Beatty, Thomas G.; Siverd, Robert J.; Lund, Michael B.; Kuhn, Rudolf B.; James, David; Gaudi, B. Scott (2018), "Variability Properties of Four Million Sources in the TESS Input Catalog Observed with the Kilodegree Extremely Little Telescope Survey", The Astronomical Journal, 155 (1): 39, arXiv: 1711.03608 , Bibcode:2018AJ....155...39O, doi: 10.3847/1538-3881/aa9bf4
10. Gontcharov, G. A. (2012), "Dependence of kinematics on the age of stars in the solar neighborhood", Astronomy Letters, 38 (12): 771, arXiv: 1606.08814 , Bibcode:2012AstL...38..771G, doi:10.1134/S1063773712120031
11. 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