HD 164604 is a single star in the southern constellation of Sagittarius constellation. It has the proper name Pincoya, as selected in the NameExoWorlds campaign by Chile, during the 100th anniversary of the IAU. Pincoya is a female water spirit from southern Chilean mythology who is said to bring drowned sailors to the Caleuche so that they can live in the afterlife.[8][9] A 2015 survey ruled out the existence of any additional stellar companions at projected distances from 13 to 340 astronomical units.[10] It is known to host a single super-Jupiter exoplanet.[11]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 18h 03m 06.93314s[1] |
| Declination | –28° 33′ 38.3576″[1] |
| Apparent magnitude (V) | 9.62[2] |
| Characteristics | |
| Spectral type | K3.5V(k)[3] |
| Apparent magnitude (B) | 11.016[2] |
| Apparent magnitude (J) | 7.784±0.024[2] |
| Apparent magnitude (H) | 7.306±0.038[2] |
| Apparent magnitude (K) | 7.169±0.020[2] |
| B−V color index | 1.396±0.491[2] |
| Astrometry | |
| Radial velocity (Rv) | 7.30±0.16[4] km/s |
| Proper motion (μ) | RA: −34.658±0.036[4] mas/yr Dec.: −42.253±0.025[4] mas/yr |
| Parallax (π) | 24.9867 ± 0.0351 mas[4] |
| Distance | 130.5 ± 0.2 ly (40.02 ± 0.06 pc) |
| Absolute magnitude (MV) | 6.57[2] |
| Details | |
| Mass | 0.77±0.04[5] M☉ |
| Radius | 0.77+0.01 −0.04[1] R☉ |
| Luminosity | 0.258±0.001[1] L☉ |
| Surface gravity (log g) | 4.41[3] cgs |
| Temperature | 4,684+135 −37[5] K |
| Metallicity [Fe/H] | 0.09±0.08[2] dex |
| Age | 7.24±4.72[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
This star is invisible to the naked eye with an apparent visual magnitude of 9.62.[2] It is located at a distance of 128.5 light years from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +6 km/s.[12] The stellar classification of HD 164604 is K3.5V(k), which indicates this is a K-type main-sequence star. The chromosphere is considered very inactive.[3] It is roughly seven[6] billion years old with 77% of the mass[5] and radius[1] of the Sun. The star is radiating 26%[1] of the luminosity of the Sun from its photosphere at an effective temperature of 4,684 K.[5]
Planetary system edit
A single super-Jupiter exoplanet was detected by the Magellan Planet Search Program in 2010 based on radial velocity variations of the host star.[11] The orbit of this body does not preclude a hypothetical Earth-mass exoplanet from occupying a dynamically stable orbit within the habitable zone of this star.[13] An astrometric measurement of the planet's inclination and true mass was published in 2022 as part of Gaia DR3.[14]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b / Caleuche | 14.3±5.5 MJ | 1.331 ± 0.0029 | 641.47 ± 10.13 | 0.35 ± 0.1 | 29±19° | — |
References edit
- ^ a b c d e f g Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e f g h i Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
- ^ a b c Gray, R. O.; et al. (July 2006). "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. S2CID 119476992.
- ^ a b c d 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.
- ^ a b c d e Feng, Fabo; et al. (June 2019). "Search for Nearby Earth Analogs. I. 15 Planet Candidates Found in PFS Data". The Astrophysical Journal Supplement Series. 242 (2): 31. arXiv:1904.08567. Bibcode:2019ApJS..242...25F. doi:10.3847/1538-4365/ab1b16. S2CID 121128472. 25.
- ^ a b Pace, G. (March 2013), "Chromospheric activity as age indicator. An L-shaped chromospheric-activity versus age diagram", Astronomy & Astrophysics, 551: 4, arXiv:1301.5651, Bibcode:2013A&A...551L...8P, doi:10.1051/0004-6361/201220364, S2CID 56420519, L8.
- ^ "HD 164604". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 5 February 2018.
- ^ "Approved names". NameExoworlds. Retrieved 2020-01-02.
- ^ "Name Exo Worlds". www.iau.org. International Astronomical Union | IAU. Retrieved 2020-01-02.
- ^ Mugrauer, M.; Ginski, C. (12 May 2015). "High-contrast imaging search for stellar and substellar companions of exoplanet host stars". Monthly Notices of the Royal Astronomical Society. 450 (3): 3127–3136. Bibcode:2015MNRAS.450.3127M. doi:10.1093/mnras/stv771. hdl:1887/49340. Retrieved 19 June 2020.
- ^ a b Arriagada, Pamela; et al. (2010). "Five Long-period Extrasolar Planets in Eccentric orbits from the Magellan Planet Search Program". The Astrophysical Journal. 711 (2): 1229–35. arXiv:1001.4093. Bibcode:2010ApJ...711.1229A. doi:10.1088/0004-637X/711/2/1229. S2CID 118682009.
- ^ Gontcharov, G. A. (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. S2CID 119231169.
- ^ Agnew, Matthew T.; et al. (November 2017). "Stable habitable zones of single Jovian planet systems". Monthly Notices of the Royal Astronomical Society. 471 (4): 4494–4507. arXiv:1706.05805. Bibcode:2017MNRAS.471.4494A. doi:10.1093/mnras/stx1449.
- ^ a b Gaia Collaboration; et al. (2023). "Gaia Data Release 3". Astronomy & Astrophysics. 674: A34. arXiv:2206.05595. doi:10.1051/0004-6361/202243782. S2CID 249626026.