HD 129445
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Circinus |
| Right ascension | 14h 46m 03.06521s[1] |
| Declination | –68° 45′ 45.8797″[1] |
| Apparent magnitude (V) | 8.80[2] |
| Characteristics | |
| Spectral type | G6 V[3] |
| Apparent magnitude (B) | 9.556[2] |
| Apparent magnitude (J) | 7.531±0.023[2] |
| Apparent magnitude (H) | 7.243±0.027[2] |
| Apparent magnitude (K) | 7.167±0.026[2] |
| B−V color index | 0.756±0.002[2] |
| Astrometry | |
| Radial velocity (Rv) | +8.56±0.13[1] km/s |
| Proper motion (μ) | RA: –197.892 mas/yr[1] Dec.: –57.069 mas/yr[1] |
| Parallax (π) | 14.9136 ± 0.0147 mas[1] |
| Distance | 218.7 ± 0.2 ly (67.05 ± 0.07 pc) |
| Absolute magnitude (MV) | 4.73[2] |
| Details[4] | |
| Mass | 1.06+0.03 −0.05 M☉ |
| Radius | 1.18±0.01[5] R☉ |
| Luminosity | 1.229+0.005 −0.004[5] L☉ |
| Surface gravity (log g) | 4.39±0.08 cgs |
| Temperature | 5,605+21 −34[5] K |
| Metallicity [Fe/H] | 0.36±0.10 dex |
| Rotational velocity (v sin i) | 1.4[6] km/s |
| Age | 4.94+3.77 −2.04 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HD 129445 (HIP 72203; LTT 5856) is a star located in the southern constellation Circinus. It has an apparent magnitude of 8.80,[2] making it faintly visble in binoculars but not to the naked eye. The object is located relatively close at a distance of 219 light-years based on Gaia DR3 parallax measurements but it is drifting away with a spectroscopic radial velocity of 8.56 km/s.[1] It has an absolute magnitude of +4.73,[2] which is similar to the Sun's absolute magnitude of 4.83.
Physical characteristics
[edit]HD 129445 has a stellar classification of G6 V,[3] indicating that it is an ordinary G-type main-sequence star like our Sun, albeit a bit cooler. It has 106% the mass of the Sun[4] and 118% the radius of the Sun.[5] It radiates 1.23 times the luminosity of the Sun from its photosphere at an effective temperature of 5,605 K,[5] giving it a yellow hue when viewed in the night sky. HD 129445 is extremely metal enriched with an iron abundance more than twice of that of the Sun's[4] and it spins slowly with a projected rotational velocity of 1.4 km/s.[6] It is slightly older than the Sun at the age of 4.94 billion years.[4]
Planetary system
[edit]The star was observed by the Magellan Planet Search Program due to its absolute visual magnitude and high metallicity. The Magellan program conducted 17 doppler velocity measurements, which spans a full orbital period. The results led the program to detect a planet dubbed HD 129445 b.[8][9][10] In 2023, the inclination and true mass of HD 129445 b were determined via astrometry.[11]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 2.51+1.1 −0.54 MJ |
2.984+0.039 −0.054 |
4.933+0.093 −0.13 |
0.572+0.087 −0.086 |
52+24 −19 or 128+19 −24° |
— |
See also
[edit]References
[edit]- ^ a b c d e f 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 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 Houk, Nancy (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 1. Ann Arbor, Michigan: Department of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H.
- ^ a b c d Aguilera-Gómez, Claudia; et al. (June 2018). "Lithium abundance patterns of late-F stars: an in-depth analysis of the lithium desert". Astronomy & Astrophysics. 614: 15. arXiv:1803.05922. Bibcode:2018A&A...614A..55A. doi:10.1051/0004-6361/201732209. S2CID 62799777. A55.
- ^ a b c d e 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 Jenkins, J. S.; et al. (July 2011). "Chromospheric activities and kinematics for solar type dwarfs and subgiants: analysis of the activity distribution and the AVR". Astronomy & Astrophysics. 531: 15. arXiv:1103.0584. Bibcode:2011A&A...531A...8J. doi:10.1051/0004-6361/201016333. S2CID 55800969. A8.
- ^ "HD 129445". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-03-22.
- ^ 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.
- ^ "Estrella del Anfitrión: HD 129445". Planet Quest. Archived from the original on 2010-07-04. Retrieved 2010-02-12.
- ^ "HD 129445". Exoplanets. Archived from the original on 2010-03-17. Retrieved 2010-02-12.
- ^ a b Xiao, Guang-Yao; Liu, Yu-Juan; et al. (May 2023). "The Masses of a Sample of Radial-Velocity Exoplanets with Astrometric Measurements". Research in Astronomy and Astrophysics. 23 (5): 055022. arXiv:2303.12409. Bibcode:2023RAA....23e5022X. doi:10.1088/1674-4527/accb7e.
