K2-19
K2-19 is a 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[2] mas |
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
Discovery
The two outer planets were reported as planet candidates during analysis of data from Campaign 1 of the Kepler spacecraft 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
K2-19 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 | ? M⊕ | 0.0344±0.0006 | 2.50856±0.00041 | ? | 85.83+2.97 −4.74° |
1.14±0.13 R⊕ |
b | 54.4±8.9 M⊕ | 0.0762±0.0022 | 7.91951+0.00040 −0.00012 |
0.023+0.240 −0.020 |
88.87+0.16 −0.60° |
7.16±0.91 R⊕ |
c | 7.5+3.0 −1.4 M⊕ |
0.1001±0.0029 | 11.9066+0.0021 −0.0014 |
0.183+0.283 −0.003 |
88.92+0.14 −0.41° |
4.34±0.55 R⊕ |
References
- 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
- Brown, A. G. A.; et al. (Gaia collaboration). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics (in press). arXiv:2012.01533. doi:10.1051/0004-6361/202039657. S2CID 227254300. Gaia EDR3 record for this source at VizieR.
- 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
- 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.
- 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.
- Skrutskie, M. F.; et al. (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
- 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.
- 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.