HD 219623

HD 219623 is the Henry Draper Catalogue designation for a solitary[9] star in the northern circumpolar constellation of Cassiopeia. It has an apparent visual magnitude of 5.59,[2] which lies in the brightness range that is visible to the naked eye. According to the Bortle scale, it can be observed from dark suburban skies. Parallax measurements made by the Hipparcos spacecraft place it at an estimated distance of around 66.9 light years.[1] It has a relatively high proper motion, advancing 262 milliarcseconds per year across the celestial sphere.[10]

HD 219623
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cassiopeia
Right ascension 23h 16m 42.30332s[1]
Declination +53° 12′ 48.5104″[1]
Apparent magnitude (V) 5.59[2]
Characteristics
Spectral type F7 V[3]
U−B color index +0.02[2]
B−V color index +0.535[2]
Astrometry
Radial velocity (Rv)−27.2[4] km/s
Proper motion (μ) RA: 111.87[1] mas/yr
Dec.: −236.51[1] mas/yr
Parallax (π)48.77 ± 0.26[1] mas
Distance66.9 ± 0.4 ly
(20.5 ± 0.1 pc)
Details
Mass1.215[5] M☉
Radius1.1950±0.0359[5] R☉
Luminosity1.9987±0.0265[5] L☉
Surface gravity (log g)4.24±0.07[6] cgs
Temperature6,138±42[6] K
Metallicity [Fe/H]+0.07±0.03[6] dex
Rotational velocity (v sin i)5.50[7] km/s
Age1.2[5] Gyr
Other designations
BD+52° 3410, GJ 4324, HD 219623, HIP 114924, HR 8853, SAO 35285.[8]
Database references
SIMBADdata

This star has a stellar classification of F7 V,[3] indicating that it is an F-type main-sequence star that is generating energy at its core through the thermonuclear fusion of hydrogen into helium. It is larger than the Sun, with 120% of the Sun's radius and 122% of the solar mass; as such, it shines nearly twice as brightly as the Sun. HD 219623 is around 1.2 billion years in age,[5] with a projected rotational velocity of 5.5 km/s.[7] Compared to the Sun, it has a slightly higher abundance of elements other than hydrogen and helium—what astronomers term the star's metallicity.[6] The effective temperature of the stellar atmosphere is about 6,138 K,[6] giving it the yellow-white hued glow of an ordinary F-type star.[11]

In 2006, this star was examined using the MIPS instrument on the Spitzer Space Telescope. An infrared excess at a wavelength of 70 μm was detected with 3-σ certainty. The data suggests the presence of circumstellar disk of orbiting dust,[12] which is likely being replenished via debris from comets or asteroids. The temperature of this dust indicates the inner edge of the disk annulus comes to within 0.4 AU of the host star, while the outer edge extends out to around 22 AU.[13]

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.
  2. Mermilliod, J.-C. (1986), Compilation of Eggen's UBV data, transformed to UBV (unpublished), SIMBAD, Bibcode:1986EgUBV........0M.
  3. Frasca, A.; et al. (December 2009), "REM near-IR and optical photometric monitoring of pre-main sequence stars in Orion. Rotation periods and starspot parameters", Astronomy and Astrophysics, 508 (3): 1313–1330, arXiv:0911.0760, Bibcode:2009A&A...508.1313F, doi:10.1051/0004-6361/200913327.
  4. Nordström, B.; et al. (May 2004), "The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ˜14,000 F and G dwarfs", Astronomy and Astrophysics, 418: 989–1019, arXiv:astro-ph/0405198, Bibcode:2004A&A...418..989N, doi:10.1051/0004-6361:20035959.
  5. Boyajian, Tabetha S.; et al. (July 2013), "Stellar Diameters and Temperatures. III. Main-sequence A, F, G, and K Stars: Additional High-precision Measurements and Empirical Relations", The Astrophysical Journal, 771 (1): 31, arXiv:1306.2974, Bibcode:2013ApJ...771...40B, doi:10.1088/0004-637X/771/1/40, 40. See Table 3.
  6. Prugniel, P.; et al. (2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv:1104.4952, Bibcode:2011A&A...531A.165P, doi:10.1051/0004-6361/201116769.
  7. Mishenina, T. V.; et al. (November 2012), "Activity and the Li abundances in the FGK dwarfs", Astronomy & Astrophysics, 547: 8, arXiv:1210.6843, Bibcode:2012A&A...547A.106M, doi:10.1051/0004-6361/201118412, A106.
  8. "HD 219623". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-03-22.
  9. Helmut A., Abt; Willmarth, Daryl (2006), "The Secondaries of Solar-Type Primaries. I. The Radial Velocities", The Astrophysical Journal Supplement Series, 162: 207–226, Bibcode:2006ApJS..162..207A, doi:10.1086/498095.
  10. Lépine, Sébastien; Shara, Michael M. (March 2005), "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)", The Astronomical Journal, 129 (3): 1483–1522, arXiv:astro-ph/0412070, Bibcode:2005AJ....129.1483L, doi:10.1086/427854.
  11. "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on March 10, 2012, retrieved 2012-01-16.
  12. Beichman, C. A.; et al. (December 2006). "New Debris Disks around Nearby Main-Sequence Stars: Impact on the Direct Detection of Planets". The Astrophysical Journal. 652 (2): 1674–1693. arXiv:astro-ph/0611682. Bibcode:2006ApJ...652.1674B. doi:10.1086/508449.
  13. Lawler, S. M.; et al. (November 2009), "Explorations Beyond the Snow Line: Spitzer/IRS Spectra of Debris Disks Around Solar-type Stars", The Astrophysical Journal, 705 (1): 89–111, arXiv:0909.0058, Bibcode:2009ApJ...705...89L, doi:10.1088/0004-637X/705/1/89.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.