Astronomy:Psi4 Aurigae
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Auriga[1] |
| Right ascension | 06h 43m 04.972s[2] |
| Declination | +44° 31′ 28.02″[2] |
| Apparent magnitude (V) | +5.02[3] |
| Characteristics | |
| Spectral type | K5 III[4] |
| U−B color index | +1.83[3] |
| B−V color index | +1.48[3] |
| Astrometry | |
| Radial velocity (Rv) | −77.35±0.23[5] km/s |
| Proper motion (μ) | RA: −4.112[2] mas/yr Dec.: −30.066[2] mas/yr |
| Parallax (π) | 10.1086 ± 0.123[2] mas |
| Distance | 323 ± 4 ly (99 ± 1 pc) |
| Absolute magnitude (MV) | +0.06[1] |
| Details | |
| Mass | 1.03+0.79−0.23[6] M☉ |
| Radius | 24.9[7] R☉ |
| Luminosity | 182+13−12[6] L☉ |
| Surface gravity (log g) | 2.04±0.24[8] cgs |
| Temperature | 4,020±80[6] K |
| Metallicity [Fe/H] | 0.10±0.08[8] dex |
| Rotational velocity (v sin i) | 4.8[5] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Psi4 Aurigae is a single,[10] orange-hued star in the northern constellation of Auriga. Its name is a Bayer designation that is Latinized from ψ4 Aurigae, and abbreviated Psi4 Aur or ψ4 Aur. This star is visible to the naked eye with an apparent visual magnitude of +5.02.[3] With an annual parallax shift of 10.11 mas,[2] it is approximately 323 light-years (99 parsecs) distant from Earth. The star is drifting closer to the Sun with a radial velocity of −77 km/s,[5] and may approach to within 102 ly (31.3 pc) in around 1.1 million years.[1]
This is a evolved K-type giant star with a stellar classification of K5 III,[4] having exhausted the hydrogen at its core. With nearly the same mass as the Sun,[6] it has expanded to 25 times the Sun's radius. The star is radiating 182 times the Sun's luminosity from its enlarged photosphere at an effective temperature of about 4,158 K.[6] It is spinning with a projected rotational velocity of 4.8 km/s.[5] This is an α–enhanced star, displaying a significant enhancement of silicon in its atmosphere.[11]
Psi4 Aurigae was part of a much bigger constellation named Telescopium Herschelii before that asterism was no longer recognized by the International Astronomical Union (IAU).[citation needed]
References
- ↑ 1.0 1.1 1.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A. XHIP record for this object at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 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.
- ↑ 3.0 3.1 3.2 3.3 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.
- ↑ 4.0 4.1 Roman, Nancy G. (July 1952), "The Spectra of the Bright Stars of Types F5-K5", Astrophysical Journal 116: 122, doi:10.1086/145598, Bibcode: 1952ApJ...116..122R.
- ↑ 5.0 5.1 5.2 5.3 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, doi:10.1088/0004-6256/135/1/209, Bibcode: 2008AJ....135..209M.
- ↑ 6.0 6.1 6.2 6.3 6.4 Charbonnel, C. et al. (January 2020), "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era", Astronomy and Astrophysics 633: A34, doi:10.1051/0004-6361/201936360, ISSN 0004-6361, Bibcode: 2020A&A...633A..34C.
- ↑ McDonald, I. et al. (October 2017), "Fundamental parameters and infrared excesses of Tycho-Gaia stars", Monthly Notices of the Royal Astronomical Society 471 (1): 770–791, doi:10.1093/mnras/stx1433, ISSN 0035-8711, Bibcode: 2017MNRAS.471..770M. Psi4 Aurigae's database entry at VizieR.
- ↑ 8.0 8.1 Prugniel, Ph. et al. (2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics 531: 25, doi:10.1051/0004-6361/201116769, A165, Bibcode: 2011A&A...531A.165P.
- ↑ "psi04 Aur". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=psi04+Aur.
- ↑ 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, Bibcode: 2008MNRAS.389..869E.
- ↑ Franchini, M. et al. (January 2004), "Synthetic Lick Indices and Detection of α-Enhanced Stars", The Astrophysical Journal 601 (1): 485–499, doi:10.1086/380443, Bibcode: 2004ApJ...601..485F
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