Astronomy:24 Vulpeculae

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Short description: Red clump giant star in the constellation Vulpecula
24 Vulpeculae
Observation data
Equinox J2000.0]] (ICRS)
Constellation Vulpecula
Right ascension  20h 16m 47.0863s[1]
Declination +24° 40′ 15.965″[1]
Apparent magnitude (V) 5.30[2]
Characteristics
Spectral type G8III[2]
B−V color index 0.951[3]
Astrometry
Radial velocity (Rv)+15.3±0.3[4] km/s
Proper motion (μ) RA: 15.128±0.055[1] mas/yr
Dec.: −17.015±0.057[1] mas/yr
Parallax (π)7.9700 ± 0.0674[1] mas
Distance409 ± 3 ly
(125 ± 1 pc)
Absolute magnitude (MV)−0.68[2]
Details[2]
Mass3.41 M
Radius16[5] R
Luminosity191 L
Surface gravity (log g)2.48 cgs
Temperature4,981 K
Metallicity [Fe/H]−0.06 dex
Rotational velocity (v sin i)5.02[3] km/s
Age251 Myr
Other designations
24 Vul, BD+24° 4075, FK5 760, HD 192944, HIP 99951, HR 7753, SAO 88451[6]
Database references
SIMBADdata

24 Vulpeculae is a single,[7] yellow-hued star in the northern constellation of Vulpecula. It is faintly visible to the naked eye with an apparent visual magnitude of 5.30.[2] The distance to this star can be estimated from its annual parallax shift of 7.9700±0.0674,[1] which yields a separation of roughly 409 light years. It is moving further away with a heliocentric radial velocity of +15 km/s.[4]

This is an evolved giant star with a stellar classification of G8III,[2] having exhausted the hydrogen at its core and moved off the main sequence. It is a red clump giant, indicating it is presently on the horizontal branch and is generating energy through helium fusion in its core region.[8] The interferometry-measured angular diameter of 24 Vul is 1.08±0.02 mas,[9] which, at its estimated distance, equates to a physical radius of about 16 times the radius of the Sun.[5]

24 Vulpeculae is about 251[2] million years old and is spinning with a projected rotational velocity of 5.02 km/s.[3] It has 3.41 times the mass of the Sun and is radiating 191 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,981 K.[2] This is the probable (99.4% chance) source of X-ray emission coming from these coordinates.[10]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Takeda, Yoichi et al. (August 2008), "Stellar Parameters and Elemental Abundances of Late-G Giants", Publications of the Astronomical Society of Japan 60 (4): 781–802, doi:10.1093/pasj/60.4.781, Bibcode2008PASJ...60..781T. 
  3. 3.0 3.1 3.2 Hekker, S.; Meléndez, J. (2007), "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters", Astronomy and Astrophysics 475 (3): 1003–1009, doi:10.1051/0004-6361:20078233, Bibcode2007A&A...475.1003H. 
  4. 4.0 4.1 Gontcharov, G. A. (2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters 32 (11): 759–771, doi:10.1134/S1063773706110065, Bibcode2006AstL...32..759G. 
  5. 5.0 5.1 Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1, https://books.google.com/books?id=OvTjLcQ4MCQC&pg=PA41 . The radius (R*) is given by:
    [math]\displaystyle{ \begin{align} 2\cdot R_* & = \frac{(10^{-3}\cdot 134\cdot 1.08)\ \text{AU}}{0.0046491\ \text{AU}/R_{\bigodot}} \\ & \approx 31.1\cdot R_{\bigodot} \end{align} }[/math]
  6. "24 Vul". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=24+Vul. 
  7. Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E. 
  8. Valentini, M.; Munari, U. (November 2010), "A spectroscopic survey of faint, high-Galactic-latitude red clump stars. I. The high resolution sample", Astronomy and Astrophysics 522: A79, doi:10.1051/0004-6361/201014870, Bibcode2010A&A...522A..79V, http://orbi.ulg.ac.be/jspui/handle/2268/142442. [yes|permanent dead link|dead link}}]
  9. Richichi, A. et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics 431 (2): 773–777, doi:10.1051/0004-6361:20042039, Bibcode2005A&A...431..773R 
  10. Haakonsen, Christian Bernt; Rutledge, Robert E. (September 2009), "XID II: Statistical Cross-Association of ROSAT Bright Source Catalog X-ray Sources with 2MASS Point Source Catalog Near-Infrared Sources", The Astrophysical Journal Supplement 184 (1): 138–151, doi:10.1088/0067-0049/184/1/138, Bibcode2009ApJS..184..138H. 

External links