Astronomy:Psi Scorpii
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 16h 12m 00.01043s[1] |
| Declination | −10° 03′ 50.8353″[1] |
| Apparent magnitude (V) | 4.94[2] |
| Characteristics | |
| Spectral type | A1 V[3] |
| U−B color index | +0.11[2] |
| B−V color index | +0.09[2] |
| Astrometry | |
| Radial velocity (Rv) | −5.10[4] km/s |
| Proper motion (μ) | RA: −18.000[1] mas/yr Dec.: −36.188[1] mas/yr |
| Parallax (π) | 20.1801 ± 0.2617[1] mas |
| Distance | 162 ± 2 ly (49.6 ± 0.6 pc) |
| Absolute magnitude (MV) | +1.55[5] |
| Orbit[6] | |
| Period (P) | 10 years |
| Semi-major axis (a) | 6.4 au |
| Details[6] | |
| ψ Sco A | |
| Mass | 1.95 M☉ |
| Radius | 2.1 R☉ |
| Luminosity | 18.6[7] L☉ |
| Surface gravity (log g) | 4.134±0.071[8] cgs |
| Temperature | 8,350 K |
| Rotational velocity (v sin i) | 42.3±0.6[9] km/s |
| Age | 630 Myr |
| ψ Sco B | |
| Mass | 0.64 M☉ |
| Radius | 0.60 R☉ |
| Temperature | 4,200 K |
| Age | 630 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Psi Scorpii, which is Latinized from ψ Scorpii, is a binary star in the zodiac constellation of Scorpius. It is white in hue and has an apparent visual magnitude of 4.94,[2] which is bright enough to be faintly visible to the naked eye. Based upon parallax measurements,[1] it is located at a distance of around 162 light years from the Sun. The system is drifting closer to the Sun with a radial velocity of −5 km/s.[4]
Characteristics
Data collected during the Hipparcos mission suggested it is an astrometric binary.[11] The companion was directly detected in 2025, with the GRAVITY instrument at VLTI. The astrometric data is consistent with an orbital period of 10 years, suggesting a separation of 3.4 astronomical units.[6]
The primary component is an A-type main sequence star with a stellar classification of A1 V;[3] a class of star that is still fusing hydrogen at its core. It has around 1.95 the mass and 2.1 times the radius of the Sun,[6] and is shining with 18.6 times the Sun's luminosity.[7] The effective temperature of the star's outer atmosphere is 8,350 K. Psi Scorpii A is around 630 million years old[6] and is spinning with a projected rotational velocity of 42.3 km/s.[12]
The secondary is has around 0.64 times the mass, 0.6 times the radius and a temperature of 4,200 K. It is 6.7 magnitudes fainter than the primary.[6]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 Hoffleit, Dorrit; Jaschek, Carlos (1991), "The Bright star catalogue", New Haven, Conn.: Yale University Observatory, 5th Rev.ed., Bibcode: 1991bsc..book.....H.
- ↑ 3.0 3.1 Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5", Michigan Spectral Survey 5, Bibcode: 1999MSS...C05....0H.
- ↑ 4.0 4.1 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, doi:10.1134/S1063773706110065, Bibcode: 2006AstL...32..759G.
- ↑ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Waisberg, Idel; Klein, Ygal; Katz, Boaz (2025-10-07), "Hidden Companions to Intermediate-mass Stars. Upgraded Multiplicity 1 → 2. XXXI. Discovery of a 0.64M ⊙, 3.4 au Companion to Psi Scorpii", Research Notes of the AAS 9 (10): 260, doi:10.3847/2515-5172/ae0e62, ISSN 2515-5172.
- ↑ 7.0 7.1 McDonald, I. et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society 427 (1): 343–57, doi:10.1111/j.1365-2966.2012.21873.x, Bibcode: 2012MNRAS.427..343M.
- ↑ Stassun, Keivan G.; Oelkers, Ryan J.; Paegert, Martin; Torres, Guillermo; Pepper, Joshua; De Lee, Nathan; Collins, Kevin; Latham, David W. et al. (2019-10-01), "The Revised TESS Input Catalog and Candidate Target List", The Astronomical Journal 158 (4): 138, doi:10.3847/1538-3881/ab3467, ISSN 0004-6256, Bibcode: 2019AJ....158..138S. Psi Scorpii's database entry at VizieR.
- ↑ Díaz, C. G. et al. (July 2011), "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum", Astronomy & Astrophysics 531: A143, doi:10.1051/0004-6361/201016386, Bibcode: 2011A&A...531A.143D.
- ↑ "psi Sco -- Star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=Psi+Sco, retrieved 2016-09-24.
- ↑ Frankowski, A. et al. (March 2007), "Proper-motion binaries in the Hipparcos catalogue. Comparison with radial velocity data", Astronomy and Astrophysics 464 (1): 377–392, doi:10.1051/0004-6361:20065526, Bibcode: 2007A&A...464..377F.
- ↑ David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal 804 (2): 146, doi:10.1088/0004-637X/804/2/146, Bibcode: 2015ApJ...804..146D.
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.
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