K2-19 is an early K-type[4] or late G-type main sequence star[5] that is magnetically active, and has a light curve that exhibits variations in brightness of ~1%.[5] It is located approximately 976 light-years away in the constellation Virgo. Three confirmed transiting exoplanets are known to orbit this star.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo[1] |
| Right ascension | 11h 39m 50.4803s[2] |
| Declination | +00° 36′ 12.875″[2] |
| Apparent magnitude (V) | 13.002±0.009[3] |
| Characteristics | |
| Spectral type | K0 V[4] or G9V[5] |
| Apparent magnitude (J) | 11.596±0.024[6] |
| Apparent magnitude (H) | 11.208±0.022[6] |
| Apparent magnitude (K) | 11.161±0.026[6] |
| Apparent magnitude (B) | 13.798±0.020[3] |
| Variable type | Planetary transit variable[7] |
| Astrometry | |
| Radial velocity (Rv) | −7.2296±0.0080[8] km/s |
| Proper motion (μ) | RA: −18.673(22)[2] mas/yr Dec.: 4.571(15)[2] mas/yr |
| Parallax (π) | 3.3410 ± 0.0196 mas[2] |
| Distance | 976 ± 6 ly (299 ± 2 pc) |
| Details[4] | |
| Mass | 0.918±0.064 M☉ |
| Radius | 0.881±0.111 R☉ |
| Surface gravity (log g) | 4.50±0.10 cgs |
| Temperature | 5250±70 K |
| Metallicity [Fe/H] | 0.10±0.05 dex |
| Rotation | 20.54±0.30 d |
| Rotational velocity (v sin i) | 3.00±0.50 km/s |
| Age | ≥8[9] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Planetary system
editDiscovery
editThe two outer planets were reported as planet candidates during analysis of data from Campaign 1 of the Kepler space telescope's K2 extended mission.[11] Both planets were confirmed by David J. Armstrong and collaborators, who used ground-based telescopes to detect additional transits and measure hour-long transit-timing variations for K2-19b.[7] They were independently validated along with 20 other planets by Benjamin T. Montet and team.[12]
K2-19d was first reported as a planet candidate during a search for candidates from the first year of the K2 Mission[13] and was later validated by Sinukoff et al.[5]
Characteristics
editK2-19 has a planetary system with three known planets, of which the two larger ones, K2-19b and K2-19c, are close to the 3:2 mean motion resonance. All three planets orbit closer to their star than the planet Mercury does to the Sun.[4][14]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| d | <10 M🜨 | 0.0344(6) | 2.5081(2) | ? | 90.8(7)° | 1.11(5) R🜨 |
| b | 32.4(1.7) M🜨 | 0.0762(22) | 7.920978(19)[16] | 0.20(3) | 91.5(1)° | 7.0(2) R🜨 |
| c | 10.8(0.6) M🜨 | 0.1001(29) | 11.8993(8) | 0.21(3) | 91.1(1)° | 4.1(2) R🜨 |
References
edit- ^ Roman, Nancy G. (1987). "Identification of a Constellation From a Position". Publications of the Astronomical Society of the Pacific. 99 (617): 695–699. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Vizier query form
- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ a b Henden, A. A.; et al. (2016). "VizieR Online Data Catalog: AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)". VizieR On-line Data Catalog: II/336. Originally Published in: 2015AAS...22533616H. 2336. Bibcode:2016yCat.2336....0H.Vizier catalog entry
- ^ a b c d Nespral, D.; et al. (2017). "Mass determination of K2-19b and K2-19c from radial velocities and transit timing variations". Astronomy and Astrophysics. 601 A128. arXiv:1604.01265. Bibcode:2017A&A...601A.128N. doi:10.1051/0004-6361/201628639. S2CID 55978628.
- ^ a b c d Sinukoff, Evan; et al. (2016). "Eleven Multiplanet Systems From K2 Campaigns 1 and 2 and the Masses of Two Hot Super-Earths". The Astrophysical Journal. 827 (1) 78. arXiv:1511.09213. Bibcode:2016ApJ...827...78S. doi:10.3847/0004-637X/827/1/78.
- ^ a b c Skrutskie, Michael F.; et al. (1 February 2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. Vizier catalog entry
- ^ a b Armstrong, David J.; et al. (2015). "One of the closest exoplanet pairs to the 3:2 mean motion resonance: K2-19b and c". Astronomy and Astrophysics. 582 A33. arXiv:1503.00692. Bibcode:2015A&A...582A..33A. doi:10.1051/0004-6361/201526008. S2CID 8463154.
- ^ a b Barros, S. C. C.; et al. (2015). "Photodynamical mass determination of the multiplanetary system K2-19". Monthly Notices of the Royal Astronomical Society. 454 (4): 4267–4276. arXiv:1510.01047. Bibcode:2015MNRAS.454.4267B. doi:10.1093/mnras/stv2271.
- ^ Narita, Norio; et al. (2015). "Characterization of the K2-19 Multiple-transiting Planetary System via High-dispersion Spectroscopy, AO Imaging, and Transit Timing Variations". The Astrophysical Journal. 815 (1) 47. arXiv:1510.01060. Bibcode:2015ApJ...815...47N. doi:10.1088/0004-637X/815/1/47.
- ^ "K2-19". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-12-31.
- ^ Foreman-Mackey, Daniel; et al. (2015). "A Systematic Search for Transiting Planets in the K2 Data". The Astrophysical Journal. 806 (2) 215. arXiv:1502.04715. Bibcode:2015ApJ...806..215F. doi:10.1088/0004-637X/806/2/215.
- ^ Montet, Benjamin T.; et al. (2015). "Stellar and Planetary Properties of K2 Campaign 1 Candidates and Validation of 17 Planets, Including a Planet Receiving Earth-like Insolation". The Astrophysical Journal. 809 (1) 25. arXiv:1503.07866. Bibcode:2015ApJ...809...25M. doi:10.1088/0004-637X/809/1/25.
- ^ Vanderburg, Andrew; et al. (2016). "Planetary Candidates from the First Year of the K2 Mission". The Astrophysical Journal Supplement Series. 222 (1) 14. arXiv:1511.07820. Bibcode:2016ApJS..222...14V. doi:10.3847/0067-0049/222/1/14.
- ^ Williams, David R. (2018-09-27). "Mercury Fact Sheet". NASA. Retrieved 2019-01-12.
- ^ Petigura, Erik A.; et al. (January 2020). "K2-19b and c are in a 3:2 Commensurability but out of Resonance: A Challenge to Planet Assembly by Convergent Migration". The Astronomical Journal. 159 (1) 2. arXiv:1910.12899. Bibcode:2020AJ....159....2P. doi:10.3847/1538-3881/ab5220.
- ^ Kokori, A.; et al. (14 February 2023). "ExoClock Project. III. 450 New Exoplanet Ephemerides from Ground and Space Observations". The Astrophysical Journal Supplement Series. 265 (1) 4. arXiv:2209.09673. Bibcode:2023ApJS..265....4K. doi:10.3847/1538-4365/ac9da4.