HIP 94292

Last updated

HIP 94292
Lyra IAU.svg
Red circle.svg
Location of HIP 94292 (circled)
Observation data
Epoch J2000.0 [1]        Equinox J2000.0 [1]
Constellation Cygnus
Right ascension 19h 11m 32.53446s
Declination +45° 31 22.6081
Apparent magnitude  (V)10.05 [2]
Characteristics
Evolutionary stage Red-giant branch star
Spectral type G8III [3]
B−V color index 0.90 [2]
J−H color index 0.474 [4]
J−K color index 0.549 [4]
Astrometry
Radial velocity (Rv)17.408899±0.007546 [5] km/s
Proper motion (μ)RA: 3.138 [1] mas/yr
Dec.: −15.988 [1] mas/yr
Parallax (π)2.4141±0.0098  mas [1]
Distance 1,351 ± 5  ly
(414 ± 2  pc)
Details [6]
Mass 1.24  M
Radius 5.636  R
Luminosity 18.759  L
Surface gravity (log g)3.029  cgs
Temperature 5069  K
Metallicity [Fe/H]−0.32±0.03 [7]   dex
Age 4.61±0.23 [8]   Gyr
Other designations
BD+45° 2850, Gaia DR3 2130219769257640576, HIP 94292, KIC 9145955, TIC 158626942, TYC 3542-2131-1, 2MASS J19113253+4531225 [4]
Database references
SIMBAD data

HIP 94292 (commonly referred to by its KIC designation KIC 9145955) is a G-type red giant branch star located 1351 light years from Earth in the northern constellation of Lyra. It is 1.24 times more massive than the Sun and has a radius of 5.636 solar radii.

Contents

It has a small scale magnetic field of 65 Gauss that is largely concentrated in the photosphere of the star.

Description

It has an apparent magnitude of 10.05, [2] which makes it too faint to observe with the naked eye, but readily visible through a 35-mm aperture telescope. [9] Gaia EDR3 parallax measurements place the star some 1,351 light-years (414 parsecs) distant, and it is receding with a heliocentric radial velocity of +17.4 km/s. [1]

HIP 94292 is an evolved giant star with a spectral type of G8III. [3] It is currently on the red-giant branch (RGB), [6] undergoing the CNO cycle within a hydrogen shell surrounding an inert core made of helium. With a radius 5.6 times that of the Sun and an effective temperature just over 5,000 K (4,730 °C; 8,540 °F), it radiates 18.8 times the luminosity of the Sun from its photosphere. [6] Due to its higher mass of 1.24 M, it is further evolved than the Sun despite a similar age of 4.61±0.23 billion years. [8]

The helium core has been precisely measured to have a mass of 0.210±0.002M and a radius of 0.0307±0.0002R. [6] As expected of RGB stars, HIP 94292 exhibits solar-like oscillations. [8]

Magnetic field

HIP 94292 was found to have small scale magnetic fields with an upper limit of around 65 Gauss that concentrates at a height of 13,100 kilometers in the photosphere of the star. [10]

See also

References

  1. 1 2 3 4 5 6 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR .
  2. 1 2 3 Høg, E.; et al. (February 2000). "The Tycho-2 Catalogue of the 2.5 Million Brightest Stars". Astronomy and Astrophysics. 355 (1): L27 –L30. Bibcode:2000A&A...355L..27H.
  3. 1 2 Molenda-Zakowicz, J.; et al. (December 2008). "Spectroscopic Study of Candidates for Kepler Asteroseismic Targets - Solar-Like Stars". Acta Astronomica. 58: 419. arXiv: 0907.0816 . Bibcode:2008AcA....58..419M.
  4. 1 2 3 "BD+45 2850". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 24 October 2024.
  5. Jönsson, Henrik; et al. (17 August 2020). "APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South". The Astronomical Journal. 160 (3). American Astronomical Society: 120. arXiv: 2007.05537 . Bibcode:2020AJ....160..120J. doi: 10.3847/1538-3881/aba592 . ISSN   0004-6256.
  6. 1 2 3 4 Zhang, Xinyi; et al. (28 February 2018). "Frequency Identification and Asteroseismic Analysis of the Red Giant KIC 9145955: Fundamental Parameters and Helium Core Size". The Astrophysical Journal. 855 (1). American Astronomical Society: 16. arXiv: 1802.01320 . Bibcode:2018ApJ...855...16Z. doi: 10.3847/1538-4357/aaaabb . ISSN   0004-637X.
  7. Pérez Hernández, F.; García, R. A.; Corsaro, E.; Triana, S. A.; De Ridder, J. (21 June 2016). "Asteroseismology of 19 low-luminosity red giant stars from Kepler". Astronomy & Astrophysics. 591. EDP Sciences: A99. arXiv: 1605.01567 . Bibcode:2016A&A...591A..99P. doi: 10.1051/0004-6361/201628311 . ISSN   0004-6361.
  8. 1 2 3 Zhang, Xinyi; et al. (1 May 2022). "Determining the Age for the Red Giants KIC 9145955 and KIC 9970396 by Gravity-dominated Mixed Modes". The Astrophysical Journal. 931 (1). American Astronomical Society: 64. Bibcode:2022ApJ...931...64Z. doi: 10.3847/1538-4357/ac695b . ISSN   0004-637X.
  9. North, Gerald; et al. (2014). Observing Variable Stars, Novae and Supernovae. Cambridge University Press. p. 24. ISBN   978-1-107-63612-5.
  10. Wang, Yuetong; Lin, Guifang; Li, Yan; Wu, Tao; Li, Yaguang (May 2025). "Asteroseismic Analysis of a Red Giant KIC 9145955 by Including the Small-scale Magnetic Fields in the Atmosphere". The Astrophysical Journal. 985 (1): 8. doi: 10.3847/1538-4357/adc71a . ISSN   0004-637X.