Location of Q Scorpii on the map (circled) | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17 36 32.85514 |
| Declination | −38° 38′ 06.8918″ |
| Apparent magnitude (V) | 4.27±0.01 |
| Characteristics | |
| Evolutionary stage | horizontal branch |
| Spectral type | K0 IIIb |
| U−B color index | +0.90 |
| B−V color index | +1.08 |
| Astrometry | |
| Radial velocity (Rv) | −49±3 km/s |
| Proper motion (μ) | RA: −16.762 mas/yr Dec.: −218.275 mas/yr |
| Parallax (π) | 20.6922 ± 0.2161 mas |
| Distance | 158 ± 2 ly (48.3 ± 0.5 pc) |
| Absolute magnitude (MV) | +0.67 |
| Details | |
| Mass | 1.10±0.07 M☉ |
| Radius | 12.39±0.47 R☉ |
| Luminosity | 62.2±4.2 L☉ |
| Surface gravity (log g) | 2.41±0.11 cgs |
| Temperature | 4,605±40 K |
| Metallicity | −0.28±0.02 dex |
| Rotational velocity (v sin i) | <1 km/s |
| Other designations | |
| Q Scorpii, 159 G. Scorpii[10], CD−38°12044, CPD−38°6933, GC 23846, HD 159433, HIP 86170, HR 6546, SAO 209019 | |
| Database references | |
| SIMBAD | data |
Q Scorpii, also designated as HD 159433, is an astrometric binary (100% chance) located in the southern zodiac constellation Scorpius. It has an apparent magnitude of 4.27, making it readily visible to the naked eye under ideal conditions. It lies in the tail of Scorpius, between the stars λ Scorpii and μ Scorpii and is located 7′ away from the faint globular cluster Tonantzintla 2. Based on parallax measurements from Gaia DR3, the system is estimated to be 158 light years distant, but is approaching the Solar System with a heliocentric radial velocity of −49 km/s.
The visible component is a red giant with a stellar classification of K0 IIIb. The IIIb luminosity class indicates that it is a lower luminosity giant star. Q Scorpii is a red clump star located on the cool end of the horizontal branch, fusing helium at its core. It has 110% the mass of the Sun but has expanded to 12.4 times its girth. It radiates 62 times the luminosity of the Sun from its photosphere at an effective temperature of 4,605 K, giving it an orange hue. Q Scorpii has an iron abundance half of the Sun's, making it metal deficient. Like most giant stars, it spins slowly, having a projected rotational velocity lower than 1 km/s.
References
- ^ Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27 – L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
- ^ Laney, C. D.; Joner, M. D.; Pietrzyński, G. (11 November 2011). "A new Large Magellanic Cloud K-band distance from precision measurements of nearby red clump stars". Monthly Notices of the Royal Astronomical Society. 419 (2): 1637–1641. arXiv:1109.4800. Bibcode:2012MNRAS.419.1637L. doi:10.1111/j.1365-2966.2011.19826.x. ISSN 0035-8711.
- ^ Hoffleit, Dorrit; Shapley, Harlow (1937). "Spectroscopic absolute magnitudes of three hundred and seventy southern stars". Annals of Harvard College Observatory. 105 (3): 45–68. Bibcode:1937AnHar.105...45H.
- ^ Cousins, A. W. J. (1971). "Photometric standard stars". Royal Observatory Annals. 7. Bibcode:1971ROAn....7.....C.
- ^ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
- Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
- ^ Ottoni, G.; Udry, S.; Ségransan, D.; Buldgen, G.; Lovis, C.; Eggenberger, P.; Pezzotti, C.; Adibekyan, V.; Marmier, M.; Mayor, M.; Santos, N. C.; Sousa, S. G.; Lagarde, N.; Charbonnel, C. (January 2022). "CORALIE radial-velocity search for companions around evolved stars (CASCADES): I. Sample definition and first results: Three new planets orbiting giant stars". Astronomy & Astrophysics. 657: A87. arXiv:2201.01528. Bibcode:2022A&A...657A..87O. doi:10.1051/0004-6361/202040078. eISSN 1432-0746. ISSN 0004-6361.
- ^ De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. eISSN 1432-0746. ISSN 0004-6361.
- Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
- "Q Scorpii". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved October 18, 2022.
- Eggleton, P. P.; Tokovinin, A. A. (11 September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. eISSN 1365-2966. ISSN 0035-8711.
- Frankowski, A.; Jancart, S.; Jorissen, A. (19 December 2006). "Proper-motion binaries in the Hipparcos catalogue". Astronomy & Astrophysics. 464 (1): 377–392. arXiv:astro-ph/0612449. Bibcode:2007A&A...464..377F. doi:10.1051/0004-6361:20065526. eISSN 1432-0746. ISSN 0004-6361.
