Astronomy:KIC 11145123

From HandWiki
Short description: Star in the constellation Cygnus
KIC 11145123
Observation data
Epoch J2000.0   Equinox (celestial coordinates)
Constellation Cygnus[1]
Right ascension  19h 41m 25.34114s[2]
Declination +48° 45′ 14.9900″[2]
Apparent magnitude (V) 13.12[3]
Characteristics
Evolutionary stage main sequence[2]
Spectral type F7V[4]
B−V color index +0.33[3]
Variable type δ Scuti[5]
Astrometry
Radial velocity (Rv)−136±4[6] km/s
Proper motion (μ) RA: −20.900[2] mas/yr
Dec.: −3.693[2] mas/yr
Parallax (π)0.8344 ± 0.01[2] mas
Distance3,910 ± 50 ly
(1,200 ± 10 pc)
Details
Mass1.46[7] M
Radius1.57±0.07[8] R
Luminosity12.6[9] L
Surface gravity (log g)4.22[9] cgs
Temperature7,590[9] K
Metallicity [Fe/H]−0.1±0.11[9] dex
Rotation≈100 days[9]
Rotational velocity (v sin i)1[9] km/s
Age756[2] Myr
Other designations
KIC 11145123, 2MASS J19412534+4845150
Database references
SIMBADdata

KIC 11145123 (sometimes mistakenly called Kepler 11145123[10]), is a white hued star located in the northern constellation Cygnus, the swan. It has an apparent magnitude of 13.12,[3] making it readily visible in large telescopes, but not to the naked eye. The object is located relatively far at a distance of approximately 3,910 light years,[2] but is rapidly approaching the Solar System with a radial velocity of −136 km/s.[6]

Characteristics

KIC 11145123 has a spectral classification of F7V,[4] indicating that it is a main sequence F-type star. Atmospheric models suggest it may be hotter and possibly a late A-type star.[5] It has 1.4 times the mass of the Sun, in contrast to the 1.7 times that would be expected from a normal late A main sequence star, and 1.57 times its radius.[8] It radiates 12 times the luminosity of the Sun from its photosphere at an effective temperature of 7,590 K.[9] Unlike most hot stars, KIC 11145123 spins exceptionally slowly with a projected rotational velocity of km/s.[9] This corresponds to a period of roughly 100 days.[9] Despite appearing as a main sequence star (Gaia DR3 models it as such),[2] it is most likely a blue straggler.[11][7]

Roundest natural object

KIC 11145123 is currently believed be the roundest natural object, with the difference between equatorial and polar radii equaling a mere three kilometers.[10]

References

  1. Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific 99 (617): 695. doi:10.1086/132034. Bibcode1987PASP...99..695R  Constellation record for this object at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  3. 3.0 3.1 3.2 Zacharias, N.; Finch, C. T.; Girard, T. M.; Henden, A.; Bartlett, J. L.; Monet, D. G.; Zacharias, M. I. (2012). "VizieR Online Data Catalog: UCAC4 Catalogue (Zacharias+, 2012)". VizieR On-line Data Catalog: I/322A. Originally Published in: 2012yCat.1322....0Z; 2013AJ....145...44Z 1322. Bibcode2012yCat.1322....0Z. 
  4. 4.0 4.1 Frasca, A.; Molenda-Żakowicz, J.; De Cat, P.; Catanzaro, G.; Fu, J. N.; Ren, A. B.; Luo, A. L.; Shi, J. R. et al. (2016). "Activity indicators and stellar parameters of the Kepler targets. An application of the ROTFIT pipeline to LAMOST-Kepler stellar spectra". Astronomy and Astrophysics 594. doi:10.1051/0004-6361/201628337. Bibcode2016A&A...594A..39F. 
  5. 5.0 5.1 Kurtz, Donald W.; Saio, Hideyuki; Takata, Masao; Shibahashi, Hiromoto; Murphy, Simon J.; Sekii, Takashi (13 August 2014). "Asteroseismic measurement of surface-to-core rotation in a main-sequence A star, KIC 11145123". Monthly Notices of the Royal Astronomical Society 444 (1): 102–116. doi:10.1093/mnras/stu1329. ISSN 0035-8711. Bibcode2014MNRAS.444..102K. 
  6. 6.0 6.1 Tsantaki, M.; Pancino, E.; Marrese, P.; Marinoni, S.; Rainer, M.; Sanna, N.; Turchi, A.; Randich, S. et al. (March 2022). "Survey of Surveys". Astronomy & Astrophysics 659: A95. doi:10.1051/0004-6361/202141702. ISSN 0004-6361. Bibcode2022A&A...659A..95T. 
  7. 7.0 7.1 Hatta, Yoshiki; Sekii, Takashi; Takata, Masao; Benomar, Othman (2021). "Nonstandard Modeling of a Possible Blue Straggler Star, KIC 11145123". The Astrophysical Journal 923 (2): 244. doi:10.3847/1538-4357/ac23c9. Bibcode2021ApJ...923..244H. 
  8. 8.0 8.1 Stassun, Keivan G. et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal 158 (4): 138. doi:10.3847/1538-3881/ab3467. Bibcode2019AJ....158..138S. 
  9. 9.0 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8 Takada-Hidai, Masahide; Kurtz, Donald W.; Shibahashi, Hiromoto; Murphy, Simon J.; Takata, Masao; Saio, Hideyuki; Sekii, Takashi (2017). "Spectroscopic and asteroseismic analysis of the remarkable main-sequence a star KIC 11145123". Monthly Notices of the Royal Astronomical Society 470 (4): 4908. doi:10.1093/mnras/stx1506. Bibcode2017MNRAS.470.4908T. 
  10. 10.0 10.1 "Kepler 11145123 is Most Spherical Natural Object Ever Seen, Astronomers Say | Astronomy | Sci-News.com" (in en-US). 18 November 2016. http://www.sci-news.com/astronomy/kepler-11145123-most-spherical-natural-object-04378.html. 
  11. Hatta, Yoshiki; Sekii, Takashi; Takata, Masao; Kurtz, Donald W. (2019). "The Two-dimensional Internal Rotation of KIC 11145123". The Astrophysical Journal 871 (2): 135. doi:10.3847/1538-4357/aaf881. Bibcode2019ApJ...871..135H.