HD 107148 is a wide binary star system in the constellation of Virgo. A pair of exoplanets have been confirmed in orbit around the brighter star. This system is located at a distance of 161 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of 25.2 K.[5] Although having an absolute magnitude of 4.47,[1] at that range the system is too faint to be visible with the naked eye, having an apparent visual magnitude of 8.01.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Virgo[1] |
| Right ascension | 12h 19m 13.491s[2] |
| Declination | −03° 19′ 11.24″[2] |
| Apparent magnitude (V) | 8.01[1] |
| Characteristics | |
| Evolutionary stage | main sequence + white dwarf |
| Spectral type | G5V[3] + DA[4] |
| B−V color index | 0.707±0.013[1] |
| Astrometry | |
| Radial velocity (Rv) | 25.244±0.0005[5] km/s |
| Proper motion (μ) | RA: −54.565 mas/yr[2] Dec.: −47.376 mas/yr[2] |
| Parallax (π) | 20.248 ± 0.0283 mas[2] |
| Distance | 161.1 ± 0.2 ly (49.39 ± 0.07 pc) |
| Absolute magnitude (MV) | 4.47[1] |
| Position (relative to HD 107148 A)[4] | |
| Component | HD 107148 B |
| Epoch of observation | 2009 |
| Angular distance | 34.9″ |
| Position angle | 174.7° |
| Projected separation | 1,790 AU |
| Details[6] | |
| HD 107148 A | |
| Mass | 1.1±0.1 M☉ |
| Radius | 1.15±0.03 R☉ |
| Luminosity | 1.34±0.05 L☉ |
| Surface gravity (log g) | 4.35±0.03 cgs |
| Temperature | 5,789±36 K |
| Metallicity [Fe/H] | 0.33±0.09[7] dex |
| Rotational velocity (v sin i) | 1.22±0.20[7] km/s |
| Age | 4±1 Gyr |
| HD 107148 B | |
| Mass | 0.6[4] M☉ |
| Temperature | 6250±250[4] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
The brighter primary member, designated component A, has a spectrum that presents as a G-type main-sequence star,[4] a yellow dwarf, with a stellar classification of G5V.[3] The star is about 4 billion years old and is spinning with a projected rotational velocity of 1.2 km/s.[7] Based on the abundance of iron, a measure of the star's metallicity, it is twice as enriched with heavy elements than the Sun. The star exhibits a magnetic activity cycle with a period around 6 years.[9] It has 1.1 times the mass of the Sun and 1.15 times the Sun's radius. HD 107148 is radiating 1.34 times the luminosity of the Sun from its photosphere at an effective temperature of 5,789 K.[6]
In 2012, a comoving white dwarf stellar companion HD 107148 B was detected[10] at projected separation of 1,790 AU, and was confirmed in 2014. It is a 0.6 M☉ remnant core of the former 1.8±0.2 M☉ star with a cooling age of 2.1±0.3 Gyr. This was formerly the primary component of this system before it ejected much of its mass.[4]
Planetary system
editIn 2006, a discovery of Saturn-mass planet was announced.[11] Another Neptune-sized planet was discovered in 2021, together with significantly refined orbit of HD 107148 b.[9]
HD 107148 should not be confused with HD 108147 located in Crux constellation, which also has an extrasolar planet discovered in 2000.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >0.196±0.009 MJ | 0.3692+0.0037 −0.0038 |
77.185+0.01 −0.025 |
0.15+0.02 −0.06 |
— | — |
| c | > 0.068+0.004 −0.005 MJ |
0.1415±0.0015 | 18.3270+0.0008 −0.0016 |
0.40+0.04 −0.08 |
— | — |
See also
editReferences
edit- ^ a b c d e f 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 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 Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.
- ^ a b c d e f Mugrauer, M.; et al. (March 2014), "New wide stellar companions of exoplanet host stars", Monthly Notices of the Royal Astronomical Society, 439 (1): 1063–1070, Bibcode:2014MNRAS.439.1063M, doi:10.1093/mnras/stu044.
- ^ a b Soubiran, C.; et al. (2018), "Gaia Data Release 2. The catalogue of radial velocity standard stars", Astronomy and Astrophysics, 616: A7, arXiv:1804.09370, Bibcode:2018A&A...616A...7S, doi:10.1051/0004-6361/201832795, S2CID 52952408.
- ^ a b Bonfanti, A.; et al. (2015), "Age consistency between exoplanet hosts and field stars", Astronomy & Astrophysics, 585: A5, arXiv:1511.01744, Bibcode:2016A&A...585A...5B, doi:10.1051/0004-6361/201527297, S2CID 53971692.
- ^ a b c Soto, M. G.; Jenkins, J. S. (July 2018), "Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue", Astronomy & Astrophysics, 615: A76, arXiv:1801.09698, Bibcode:2018A&A...615A..76S, doi:10.1051/0004-6361/201731533, A76.
- ^ "HD 107148". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-11-12.
- ^ a b Rosenthal, Lee J.; et al. (2021), "The California Legacy Survey. I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades", The Astrophysical Journal Supplement Series, 255 (1): 8, arXiv:2105.11583, Bibcode:2021ApJS..255....8R, doi:10.3847/1538-4365/abe23c, S2CID 235186973.
- ^ Tokovinin, Andrei; Lépine, Sébastien (October 2012), "Wide companions to Hipparcos stars within 67 pc of the Sun", The Astronomical Journal, 144 (4): 102, arXiv:1208.0626, Bibcode:2012AJ....144..102T, doi:10.1088/0004-6256/144/4/102, 102.
- ^ Butler, R. P.; et al. (2006), "Catalog of Nearby Exoplanets", The Astrophysical Journal, 646 (1): 505–522, arXiv:astro-ph/0607493, Bibcode:2006ApJ...646..505B, doi:10.1086/504701, S2CID 119067572.
- ^ Eberhardt, Jan; et al. (2022), "Dynamical Architecture of the HD 107148 Planetary System", The Astronomical Journal, 163 (5): 198, arXiv:2202.06702, Bibcode:2022AJ....163..198E, doi:10.3847/1538-3881/ac53b2, S2CID 246822760.