Astronomy:Chi1 Orionis
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Orion |
| Right ascension | 05h 54m 22.98s[1] |
| Declination | +20° 16′ 34.2″[1] |
| Apparent magnitude (V) | 4.38 - 4.41[2] |
| Characteristics | |
| Spectral type | G0 V[3] |
| U−B color index | +0.07[4] |
| B−V color index | +0.59[4] |
| Variable type | RS CVn[2] |
| Astrometry | |
| Radial velocity (Rv) | −15.42[5] km/s |
| Proper motion (μ) | RA: −162.54±0.28[1] mas/yr Dec.: −99.51±0.16[1] mas/yr |
| Parallax (π) | 115.43 ± 0.27[1] mas |
| Distance | 28.26 ± 0.07 ly (8.66 ± 0.02 pc) |
| Absolute magnitude (MV) | 4.82±0.005[6] |
| Orbit[7] | |
| Period (P) | 5156.291±2.508 d |
| Semi-major axis (a) | 89.662±0.880 Mas |
| Eccentricity (e) | 0.452±0.002 |
| Inclination (i) | 95.937±0.790° |
| Longitude of the node (Ω) | 126.360±0.593° |
| Periastron epoch (T) | 2451468.2±3.083 JD |
| Argument of periastron (ω) (secondary) | 111.527±0.230° |
| Semi-amplitude (K1) (primary) | 1.876±0.003 km/s |
| Details | |
| primary | |
| Mass | 1.01[8] M☉ |
| Radius | 0.979±0.009[9] R☉ |
| Luminosity | 1.081±0.018[9] L☉ |
| Surface gravity (log g) | 4.39[8] cgs |
| Temperature | 5,955±6.1[10] K |
| Metallicity [Fe/H] | −0.01[11] dex |
| Rotation | 5.2 days[11] |
| Rotational velocity (v sin i) | 8.7[8] km/s |
| Age | 300–400[12] Myr |
| companion | |
| Mass | 0.15[8] M☉ |
| Age | 70-130[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Chi1 Orionis (χ1 Ori, χ1 Orionis) is a star about 28 light years away.[1] It is in the constellation Orion, where it can be seen in the tip of the hunter's upraised club.[13]
χ1 Ori is a G0V star.[8] It is listed in the General Catalog of Variable Stars as an RS Canum Venaticorum variable, varying between visual magnitude 4.38 and 4.41.[2] Stępień and Geyer measured its period to be 5.5 days.[15]
χ1 Ori has a faint companion with a mass estimated at about 15% of the mass of the Sun, and an orbital period of 14.1 years. The companion orbits an average distance of 6.1 AU from the primary, but has a fairly high orbital eccentricity, ranging from 3.3 AU out to 8.9 AU from the primary. Because of this red dwarf companion, the likelihood of habitable planets in this system is low. It is thought that the companion is a red dwarf still contracting towards the main sequence.[8]
A necessary condition for the existence of a planet in this system are stable zones where the object can remain in orbit for long intervals. For hypothetical planets in a circular orbit around the individual members of this star system, this maximum orbital radius is computed to be 1.01 AU for the primary and 0.41 AU for the secondary. (Note that the orbit of the Earth is 1 AU from the Sun.) A planet orbiting outside of both stars would need to be at least 18.4 AU distant.[16]
χ1 Ori is a candidate stream star member of the Ursa Major Moving Group, although there is some evidence to the contrary.[11]
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V. Vizier catalog entry
- ↑ 2.0 2.1 2.2 "khi 1 Ori". Sternberg Astronomical Institute. http://www.sai.msu.su/gcvs/cgi-bin/search2.cgi?search=khi+1+Ori.
- ↑ Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". The Astrophysical Journal Supplement Series 71: 245. doi:10.1086/191373. Bibcode: 1989ApJS...71..245K.
- ↑ 4.0 4.1 Hoffleit, Dorrit; Jaschek, Carlos (1991). "The Bright star catalogue". New Haven, Conn.: Yale University Observatory, 5th Rev.ed.. Bibcode: 1991bsc..book.....H.
- ↑ 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.
- ↑ Park, Sunkyung et al. (2013). "Wilson-Bappu Effect: Extended to Surface Gravity". The Astronomical Journal 146 (4): 73. doi:10.1088/0004-6256/146/4/73. Bibcode: 2013AJ....146...73P.
- ↑ Han, Inwoo; Gatewood, George (2002). "A Precise Orbit Determination of χ1Orionis from Astrometric and Radial Velocity Data". Publications of the Astronomical Society of the Pacific 114 (792): 224–228. doi:10.1086/338367. Bibcode: 2002PASP..114..224H.
- ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 König, B.; Fuhrmann, K.; Neuhäuser, R.; Charbonneau, D.; Jayawardhana, R. (2002). "Direct detection of the companion of chi 1 Orionis". Astronomy and Astrophysics 394. doi:10.1051/0004-6361:20021377. Bibcode: 2002A&A...394L..43K.
- ↑ 9.0 9.1 Boyajian, Tabetha S. et al. (February 2012). "Stellar Diameters and Temperatures. I. Main-sequence A, F, and G Stars". The Astrophysical Journal 746 (1): 101. doi:10.1088/0004-637X/746/1/101. Bibcode: 2012ApJ...746..101B.. See Table 10.
- ↑ Kovtyukh (2003). "High precision effective temperatures for 181 F-K dwarfs from line-depth ratios". Astronomy and Astrophysics 411 (3): 559–564. doi:10.1051/0004-6361:20031378. Bibcode: 2003A&A...411..559K.
- ↑ 11.0 11.1 11.2 Maldonado, J. et al. (October 2010). "A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups". Astronomy and Astrophysics 521: A12. doi:10.1051/0004-6361/201014948. Bibcode: 2010A&A...521A..12M.
- ↑ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal 687 (2): 1264–1293. doi:10.1086/591785. Bibcode: 2008ApJ...687.1264M.
- ↑ Jim Kaler. "Chi-1 Orionis". http://stars.astro.illinois.edu/sow/chi1ori.html.
- ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html.
- ↑ Stępień, K.; Geyer, E. (May 1996). "Rotation of solar-like main sequence stars". Astronomy and Astrophysics Supplement 117: 83–91. doi:10.1051/aas:1996141. Bibcode: 1996A&AS..117...83S.
- ↑ Jaime, Luisa G. et al. (December 2012). "Regions of dynamical stability for discs and planets in binary stars of the solar neighbourhood". Monthly Notices of the Royal Astronomical Society 427 (4): 2723–2733. doi:10.1111/j.1365-2966.2012.21839.x. Bibcode: 2012MNRAS.427.2723J.
External links
- Chi-1 Orionis by Professor Jim Kaler.
- Chi1 Orionis 2 at SolStation.
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