HD 45184 is a star in the southern constellation of Canis Major. It is a yellow-hued star near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.37.[2] The star is located at a distance of 71.65 light years from the Sun based on parallax.[1] It is drifting closer with a radial velocity of −3.8 km/s.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 06h 24m 43.87975s[1] |
| Declination | –28° 46′ 48.4163″[1] |
| Apparent magnitude (V) | 6.37[2] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | G2Va[3] |
| Apparent magnitude (B) | 6.996[2] |
| Apparent magnitude (J) | 5.219[4] |
| Apparent magnitude (H) | 4.962[4] |
| Apparent magnitude (K) | 4.871[4] |
| B−V color index | 0.626±0.007[2] |
| Astrometry | |
| Radial velocity (Rv) | −3.828±0.0003[1] km/s |
| Proper motion (μ) | RA: −165.257[1] mas/yr Dec.: −121.826[1] mas/yr |
| Parallax (π) | 45.5224 ± 0.0320 mas[1] |
| Distance | 71.65 ± 0.05 ly (21.97 ± 0.02 pc) |
| Absolute magnitude (MV) | 4.67[2][5] |
| Details | |
| Mass | 1.08±0.04[6] M☉ |
| Radius | 1.05±0.02[1] R☉ |
| Luminosity | 1.178+0.002 −0.001[1] L☉ |
| Surface gravity (log g) | 4.47±0.02[7] cgs |
| Temperature | 5,862+72 −48[1] K |
| Metallicity [Fe/H] | 0.070±0.016[6] dex |
| Rotation | 20.0±0.1 d[6] |
| Rotational velocity (v sin i) | 2.1[7] km/s |
| Age | 3.0+0.7 −1.4[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
This object is an ordinary G-type main-sequence star with a stellar classification of G2Va,[3] and it is considered a solar twin.[5] The mass, size, and luminosity of the star are slightly higher than for the Sun, and it has a near solar metallicity – what astronomers term the abundance of elements with higher atomic numbers than helium. The star is around three billion years old and is spinning with a 20-day period.[6] It has a 5.14[9]-year magnetic activity cycle that has a lower amplitude than on the Sun.[7]
Planetary system
editHD 45184 has a planet around 12 times as massive as Earth that takes 5.88 days to complete an orbit around its host star. This planet was detected using the radial velocity method.[10] It was later confirmed with Spitzer, whereupon a second candidate planet of similar mass was discovered orbiting with a 13.1 day period. The star was observed by Spitzer for a transit of the inner planet, but no event was detected.[11] Both Neptune-like planets have near circular orbits close to the host star.[7]
An infrared excess has been detected using the Multiband Imaging Photometer for Spitzer at a wavelength of 70 μm, making this a debris disk candidate.[12] Based upon blackbody models, it is orbiting 1.0 AU from the host star with a mean temperature of 280 K. There may be an additional, 60 K debris disk orbiting at a distance of 22.89 AU.[13]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥12.19+1.06 −1.03 M🜨 |
0.0644+0.0020 −0.0021 |
5.8854±0.0003 | 0.07±0.05 | — | — |
| c | ≥8.81+1.09 −1.02 M🜨 |
0.1100+0.0034 −0.0036 |
13.1354+0.0026 −0.0025 |
0.07+0.07 −0.05 |
— | — |
References
edit- ^ a b c d e f g h i j k 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 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 Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373. S2CID 123149047.
- ^ a b c Cutri, R. M.; et al. (June 2003). 2MASS All Sky Catalog of point sources. NASA/IPAC. Bibcode:2003tmc..book.....C.
- ^ a b Datson, Juliet; et al. (March 2014). "Solar analogues and solar twins in the HARPS archive". Monthly Notices of the Royal Astronomical Society. 439 (1): 1028–1037. arXiv:1401.1316. Bibcode:2014MNRAS.439.1028D. doi:10.1093/mnras/stu026.
- ^ a b c d e Lorenzo-Oliveira, Diego; et al. (May 2019). "Constraining the evolution of stellar rotation using solar twins". Monthly Notices of the Royal Astronomical Society: Letters. 485 (1): L68–L72. arXiv:1903.02630. Bibcode:2019MNRAS.485L..68L. doi:10.1093/mnrasl/slz034.
- ^ a b c d e Udry, S.; et al. (February 2019). "The HARPS search for southern extra-solar planets. XLIV. Eight HARPS multi-planet systems hosting 20 super-Earth and Neptune-mass companions". Astronomy & Astrophysics. 622: 29. arXiv:1705.05153. Bibcode:2019A&A...622A..37U. doi:10.1051/0004-6361/201731173. S2CID 119095511. A37.
- ^ "HD 45184". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-02.
- ^ Flores, M.; et al. (May 2016). "Discovery of an activity cycle in the solar analog HD 45184. Exploring Balmer and metallic lines as activity proxy candidates". Astronomy & Astrophysics. 589: 6. arXiv:1604.01307. Bibcode:2016A&A...589A.135F. doi:10.1051/0004-6361/201628145. S2CID 119280028. A135.
- ^ Mayor, M.; et al. (2011). "The HARPS search for southern extra-solar planets XXXIV. Occurrence, mass distribution and orbital properties of super-Earths and Neptune-mass planets". arXiv:1109.2497. Bibcode:2011arXiv1109.2497M.
{{cite journal}}: Cite journal requires|journal=(help) - ^ Gillon, M.; et al. (2017). "The Spitzer search for the transits of HARPS low-mass planets. II. Null results for 19 planets". Astronomy and Astrophysics. 601. A117. arXiv:1701.01303. Bibcode:2017A&A...601A.117G. doi:10.1051/0004-6361/201629270. S2CID 86862862.
- ^ Koerner, D. W.; et al. (February 2010). "New Debris Disk Candidates Around 49 Nearby Stars" (PDF). The Astrophysical Journal Letters. 710 (1): L26–L29. Bibcode:2010ApJ...710L..26K. doi:10.1088/2041-8205/710/1/L26.
- ^ Cotten, Tara H.; Song, Inseok (July 2016). "A Comprehensive Census of Nearby Infrared Excess Stars". The Astrophysical Journal Supplement Series. 225 (1): 24. arXiv:1606.01134. Bibcode:2016ApJS..225...15C. doi:10.3847/0067-0049/225/1/15. S2CID 118438871. 15.