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Mu Aquilae

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Mu Aquilae
Location of μ Aquilae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 19h 34m 05.3529s[1]
Declination +07° 22′ 44.189″[1]
Apparent magnitude (V) 4.45[2]
Characteristics
Spectral type K3-IIIb Fe0.5[3]
U−B color index +1.24[2]
B−V color index +1.176[4]
R−I color index 0.61
Astrometry
Radial velocity (Rv)−24.73±0.13[5] km/s
Proper motion (μ) RA: +213.73[1] mas/yr
Dec.: −156.55[1] mas/yr
Parallax (π)30.31 ± 0.24 mas[1]
Distance107.6 ± 0.9 ly
(33.0 ± 0.3 pc)
Absolute magnitude (MV)1.80[5]
Details[6]
Mass1.16±0.10 M
Radius7.43±0.15[7] R
Luminosity24.5 L
Surface gravity (log g)2.70±0.06 cgs
Temperature4,567±79 K
Metallicity [Fe/H]0.16 dex
Rotational velocity (v sin i)0.0[4] km/s
Age6.71±2.19 Gyr
Other designations
μ Aql, 38 Aql, BD+07 4132, FK5 1511, GJ 9661, HD 184406, HIP 96229, HR 7429, SAO 124799, LTT 15709[8]
Database references
SIMBADdata

Mu Aquilae, Latinized from μ Aquilae, is the Bayer designation for a single[9] star in the equatorial constellation of Aquila. With an apparent visual magnitude of 4.45,[2] it is visible to the naked eye. The measured annual parallax shift of this star is 30.31 mas,[1] which gives a distance estimate of 107.6 light-years (33.0 parsecs) from Earth. It is drifting closer with a radial velocity of −25 km/s,[5] and displays a relatively high proper motion, traversing the celestial sphere at the rate of 0.264 per year.[10]

The stellar classification of Mu Aquilae is K3-IIIb Fe0.5,[3] indicating that this is an evolved giant star with a mild overabundance of iron appearing in its spectrum. It belongs to a sub-category of giants called the red clump, which means it is generating energy through the fusion of helium at its core.[11] Compared to the Sun, it has 116% of the mass and has expanded to 7.7 times the size. This inflated outer envelope has an effective temperature of 4,567 K and is radiating 24.5 times the Sun's luminosity.[6] At this heat, Mu Aquilae glows with the orange hue of a K-type star.[12] It is roughly seven billion years old.[6]

References

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  1. ^ a b c d e f van Leeuwen, F. (November 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 18759600.
  2. ^ a b c Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
  3. ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", The Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
  4. ^ a b Massarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity", The Astronomical Journal, 135 (1): 209–231, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209, S2CID 121883397.
  5. ^ a b c Hekker, S.; et al. (August 2006), "Precise radial velocities of giant stars. I. Stable stars", Astronomy and Astrophysics, 454 (3): 943–949, arXiv:astro-ph/0604502, Bibcode:2006A&A...454..943H, doi:10.1051/0004-6361:20064946, S2CID 119529768
  6. ^ a b c Maldonado, J.; et al. (June 2013), "The metallicity signature of evolved stars with planets", Astronomy & Astrophysics, 554: 18, arXiv:1303.3418, Bibcode:2013A&A...554A..84M, doi:10.1051/0004-6361/201321082, S2CID 119289111, A84.
  7. ^ Baines, Ellyn K.; Clark, James H., III; Schmitt, Henrique R.; Stone, Jordan M.; von Braun, Kaspar (2023-12-01). "33 New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble". The Astronomical Journal. 166 (6): 268. Bibcode:2023AJ....166..268B. doi:10.3847/1538-3881/ad08be. ISSN 0004-6256.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. ^ "* mu. Aql", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2012-07-18.
  9. ^ Eggleton, Peter; Tokovinin, A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  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, S2CID 2603568.
  11. ^ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.
  12. ^ "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on March 18, 2012, retrieved 2012-01-16.
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