Astronomy:Chi Scorpii
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 16h 13m 50.906s[1] |
| Declination | −11° 50′ 15.89″[1] |
| Apparent magnitude (V) | 5.24[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch(57%chance) or red giant branch(43%chance)[3] |
| Spectral type | K3 III[4] |
| U−B color index | +1.54[5] |
| B−V color index | +1.39[2] |
| Astrometry | |
| Radial velocity (Rv) | −23.61±0.1[6] km/s |
| Proper motion (μ) | RA: −4.991[1] mas/yr Dec.: −9.931[1] mas/yr |
| Parallax (π) | 7.2874 ± 0.0993[1] mas |
| Distance | 448 ± 6 ly (137 ± 2 pc) |
| Absolute magnitude (MV) | −0.08[2] |
| Details[3] | |
| Mass | 1.22+0.13 −0.14 M☉ |
| Radius | 25.92+0.78 −0.74 R☉ |
| Luminosity | 179.62+11.10 −9.55 L☉ |
| Surface gravity (log g) | 1.66±0.05 cgs |
| Temperature | 4,157+11 −10 K |
| Metallicity [Fe/H] | −0.01±0.10 dex |
| Rotational velocity (v sin i) | 8[7] km/s |
| Age | 8.39±2.64 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Chi Scorpii, Latinized from χ Scorpii, is a single[9] star in the zodiac constellation of Scorpius. It has an orange hue and can be faintly seen with the naked eye with an apparent visual magnitude of 5.24.[2][5] Based upon parallax measurements, this star is around 448 light years from the Sun.[1] The star is drifting closer with a radial velocity of −23.6 km/s.[6]
This is an aging K-type giant star with a stellar classification of K3 III,[4] which means it has exhausted the supply of hydrogen at its core. There is a 57% chance that this evolved star is on the horizontal branch and a 43% chance it is still on the red-giant branch. If it is on the former, the star is estimated to have 1.09 times the mass of the Sun, nearly 27 times the solar radius and shines with 191 times the Sun's luminosity. It is around 8 billion years old.[3]
Planetary system
One superjovian planet orbiting Chi Scorpii was detected in 2020 on a mildly eccentric orbit utilizing a radial velocity method.[10][11]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥4.32+0.15−0.12 MJ | 1.45±0.02 | 573.4±2.0 | 0.06+0.03−0.02 | — | — |
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 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.
- ↑ 2.0 2.1 2.2 2.3 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 3.0 3.1 3.2 Reffert, Sabine et al. (2015), "Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity", Astronomy & Astrophysics 574: A116, doi:10.1051/0004-6361/201322360, Bibcode: 2015A&A...574A.116R. Values are for the slightly higher probability horizontal branch model fit.
- ↑ 4.0 4.1 Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey 5, Bibcode: 1999MSS...C05....0H.
- ↑ 5.0 5.1 Mermilliod, J.-C. (1986), Compilation of Eggen's UBV data, transformed to UBV (unpublished), SIMBAD, Bibcode: 1986EgUBV........0M.
- ↑ 6.0 6.1 Nidever, David L. et al. (August 2002), "Radial Velocities for 889 Late-Type Stars", The Astrophysical Journal Supplement Series 141 (2): 503–522, doi:10.1086/340570, Bibcode: 2002ApJS..141..503N.
- ↑ Bernacca, P. L.; Perinotto, M. (1970), "A catalogue of stellar rotational velocities", Contributi Osservatorio Astronomico di Padova in Asiago 239 (1), Bibcode: 1970CoAsi.239....1B.
- ↑ "chi Sco -- Star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Chi+Sco, retrieved 2016-09-24.
- ↑ 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.
- ↑ Pinto, Marcelo Tala; Reffert, Sabine; Quirrenbach, Andreas; Stock, Stephan; Trifonov, Trifon; Mitchell, David S. (2020). "Precise radial velocities of giant stars". Astronomy & Astrophysics 644: A1. doi:10.1051/0004-6361/202038285.
- ↑ Marcelo, Tala Pinto (December 2020). "Precise radial velocities of giant stars. XIV. Evidence of planetary companions around HD 25723, 17 Sco, 3 Cnc, and 44 UMa". Astronomy & Astrophysics 644 (A1): 13. https://www.aanda.org/articles/aa/pdf/2020/12/aa38285-20.pdf.
- ↑ 17 Sco b on exoplanet.eu
External links
- Kaler, James B. (August 12, 2016), "Chi and Psi Scorpii", Stars (University of Illinois), http://stars.astro.illinois.edu/Sow/chisco.html, retrieved 2016-09-25.
 |  |
