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]
↑ 3.03.1Henden, 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...22533616H2336. Bibcode: 2016yCat.2336....0H.Vizier catalog entry
↑ 8.08.1Barros, S. C. C. et al. (2015). "Photodynamical mass determination of the multiplanetary system K2-19". Monthly Notices of the Royal Astronomical Society454 (4): 4267–4276. doi:10.1093/mnras/stv2271. Bibcode: 2015MNRAS.454.4267B.
↑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 Journal815 (1). doi:10.1088/0004-637X/815/1/47. Bibcode: 2015ApJ...815...47N.
↑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 Journal809 (1). doi:10.1088/0004-637X/809/1/25. Bibcode: 2015ApJ...809...25M.
↑Petigura, Erik A. et al. (10 December 2019). "K2-19b and c are in a 3:2 Commensurability but out of Resonance: A Challenge to Planet Assembly by Convergent Migration". The Astronomical Journal159 (1). doi:10.3847/1538-3881/ab5220. Bibcode: 2020AJ....159....2P.