Astronomy:HIP 94292
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| 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[1] mas |
| 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 | |
| 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.
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±0.002 M☉ and a radius of 0.0307±0.0002 R☉.[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
- KIC 9970396: a similar red giant in an eclipsing binary.
References
- ↑ 1.0 1.1 1.2 1.3 1.4 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. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 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.
- ↑ 3.0 3.1 Molenda-Zakowicz, J. et al. (December 2008). "Spectroscopic Study of Candidates for Kepler Asteroseismic Targets - Solar-Like Stars". Acta Astronomica 58: 419. Bibcode: 2008AcA....58..419M.
- ↑ 4.0 4.1 4.2 "BD+45 2850". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=BD%2B45+2850.
- ↑ Jönsson, Henrik et al. (2020-08-17). "APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South". The Astronomical Journal (American Astronomical Society) 160 (3): 120. doi:10.3847/1538-3881/aba592. ISSN 0004-6256. Bibcode: 2020AJ....160..120J.
- ↑ 6.0 6.1 6.2 6.3 Zhang, Xinyi et al. (2018-02-28). "Frequency Identification and Asteroseismic Analysis of the Red Giant KIC 9145955: Fundamental Parameters and Helium Core Size". The Astrophysical Journal (American Astronomical Society) 855 (1): 16. doi:10.3847/1538-4357/aaaabb. ISSN 0004-637X. Bibcode: 2018ApJ...855...16Z.
- ↑ Pérez Hernández, F.; García, R. A.; Corsaro, E.; Triana, S. A.; De Ridder, J. (2016-06-21). "Asteroseismology of 19 low-luminosity red giant stars from Kepler". Astronomy & Astrophysics (EDP Sciences) 591: A99. doi:10.1051/0004-6361/201628311. ISSN 0004-6361. Bibcode: 2016A&A...591A..99P.
- ↑ 8.0 8.1 8.2 Zhang, Xinyi et al. (2022-05-01). "Determining the Age for the Red Giants KIC 9145955 and KIC 9970396 by Gravity-dominated Mixed Modes". The Astrophysical Journal (American Astronomical Society) 931 (1): 64. doi:10.3847/1538-4357/ac695b. ISSN 0004-637X. Bibcode: 2022ApJ...931...64Z.
- ↑ North, Gerald et al. (2014). Observing Variable Stars, Novae and Supernovae. Cambridge University Press. p. 24. ISBN 978-1-107-63612-5. https://books.google.com/books?id=IzoDBAAAQBAJ&pg=PA24.
- ↑ 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" (in en). The Astrophysical Journal 985 (1): 8. doi:10.3847/1538-4357/adc71a. ISSN 0004-637X.
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