_version_ 1866914964046872576
author Masuda, Kento
Libby-Roberts, Jessica E.
Livingston, John H.
Stevenson, Kevin B.
Gao, Peter
Vissapragada, Shreyas
Fu, Guangwei
Han, Te
Greklek-McKeon, Michael
Mahadevan, Suvrath
Agol, Eric
Bello-Arufe, Aaron
Berta-Thompson, Zachory
Canas, Caleb I.
Chachan, Yayaati
Hebb, Leslie
Hu, Renyu
Kawashima, Yui
Knutson, Heather A.
Morley, Caroline V.
Murray, Catriona A.
Ohno, Kazumasa
Tokadjian, Armen
Zhang, Xi
Welbanks, Luis
Nixon, Matthew C.
Freedman, Richard
Narita, Norio
Fukui, Akihiko
de Leon, Jerome P.
Mori, Mayuko
Palle, Enric
Murgas, Felipe
Parviainen, Hannu
Esparza-Borges, Emma
Jontof-Hutter, Daniel
Collins, Karen A.
Benni, Paul
Barkaoui, Khalid
Pozuelos, Francisco J.
Gillon, Michael
Jehin, Emmanuel
Benkhaldoun, Zouhair
Hawley, Suzanne
Lin, Andrea S. J.
Stefansson, Gudmundur
Bieryla, Allyson
Yilmaz, Mesut
Senavci, Hakan Volkan
Girardin, Eric
Marino, Giuseppe
Wang, Gavin
author_facet Masuda, Kento
Libby-Roberts, Jessica E.
Livingston, John H.
Stevenson, Kevin B.
Gao, Peter
Vissapragada, Shreyas
Fu, Guangwei
Han, Te
Greklek-McKeon, Michael
Mahadevan, Suvrath
Agol, Eric
Bello-Arufe, Aaron
Berta-Thompson, Zachory
Canas, Caleb I.
Chachan, Yayaati
Hebb, Leslie
Hu, Renyu
Kawashima, Yui
Knutson, Heather A.
Morley, Caroline V.
Murray, Catriona A.
Ohno, Kazumasa
Tokadjian, Armen
Zhang, Xi
Welbanks, Luis
Nixon, Matthew C.
Freedman, Richard
Narita, Norio
Fukui, Akihiko
de Leon, Jerome P.
Mori, Mayuko
Palle, Enric
Murgas, Felipe
Parviainen, Hannu
Esparza-Borges, Emma
Jontof-Hutter, Daniel
Collins, Karen A.
Benni, Paul
Barkaoui, Khalid
Pozuelos, Francisco J.
Gillon, Michael
Jehin, Emmanuel
Benkhaldoun, Zouhair
Hawley, Suzanne
Lin, Andrea S. J.
Stefansson, Gudmundur
Bieryla, Allyson
Yilmaz, Mesut
Senavci, Hakan Volkan
Girardin, Eric
Marino, Giuseppe
Wang, Gavin
contents Kepler-51 is a $\lesssim 1\,\mathrm{Gyr}$-old Sun-like star hosting three transiting planets with radii $\approx 6$-$9\,R_\oplus$ and orbital periods $\approx 45$-$130\,\mathrm{days}$. Transit timing variations (TTVs) measured with past Kepler and Hubble Space Telescope (HST) observations have been successfully modeled by considering gravitational interactions between the three transiting planets, yielding low masses and low mean densities ($\lesssim 0.1\,\mathrm{g/cm^3}$) for all three planets. However, the transit time of the outermost transiting planet Kepler-51d recently measured by the James Webb Space Telescope (JWST) 10 years after the Kepler observations is significantly discrepant from the prediction made by the three-planet TTV model, which we confirmed with ground-based and follow-up HST observations. We show that the departure from the three-planet model is explained by including a fourth outer planet, Kepler-51e, in the TTV model. A wide range of masses ($\lesssim M_\mathrm{Jup}$) and orbital periods ($\lesssim 10\,\mathrm{yr}$) are possible for Kepler-51e. Nevertheless, all the coplanar solutions found from our brute-force search imply masses $\lesssim 10\,M_\oplus$ for the inner transiting planets. Thus their densities remain low, though with larger uncertainties than previously estimated. Unlike other possible solutions, the one in which Kepler-51e is around the $2:1$ mean motion resonance with Kepler-51d implies low orbital eccentricities ($\lesssim 0.05$) and comparable masses ($\sim 5\,M_\oplus$) for all four planets, as is seen in other compact multi-planet systems. This work demonstrates the importance of long-term follow-up of TTV systems for probing longer period planets in a system.
format Preprint
id arxiv_https___arxiv_org_abs_2410_01625
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A Fourth Planet in the Kepler-51 System Revealed by Transit Timing Variations
Masuda, Kento
Libby-Roberts, Jessica E.
Livingston, John H.
Stevenson, Kevin B.
Gao, Peter
Vissapragada, Shreyas
Fu, Guangwei
Han, Te
Greklek-McKeon, Michael
Mahadevan, Suvrath
Agol, Eric
Bello-Arufe, Aaron
Berta-Thompson, Zachory
Canas, Caleb I.
Chachan, Yayaati
Hebb, Leslie
Hu, Renyu
Kawashima, Yui
Knutson, Heather A.
Morley, Caroline V.
Murray, Catriona A.
Ohno, Kazumasa
Tokadjian, Armen
Zhang, Xi
Welbanks, Luis
Nixon, Matthew C.
Freedman, Richard
Narita, Norio
Fukui, Akihiko
de Leon, Jerome P.
Mori, Mayuko
Palle, Enric
Murgas, Felipe
Parviainen, Hannu
Esparza-Borges, Emma
Jontof-Hutter, Daniel
Collins, Karen A.
Benni, Paul
Barkaoui, Khalid
Pozuelos, Francisco J.
Gillon, Michael
Jehin, Emmanuel
Benkhaldoun, Zouhair
Hawley, Suzanne
Lin, Andrea S. J.
Stefansson, Gudmundur
Bieryla, Allyson
Yilmaz, Mesut
Senavci, Hakan Volkan
Girardin, Eric
Marino, Giuseppe
Wang, Gavin
Earth and Planetary Astrophysics
Kepler-51 is a $\lesssim 1\,\mathrm{Gyr}$-old Sun-like star hosting three transiting planets with radii $\approx 6$-$9\,R_\oplus$ and orbital periods $\approx 45$-$130\,\mathrm{days}$. Transit timing variations (TTVs) measured with past Kepler and Hubble Space Telescope (HST) observations have been successfully modeled by considering gravitational interactions between the three transiting planets, yielding low masses and low mean densities ($\lesssim 0.1\,\mathrm{g/cm^3}$) for all three planets. However, the transit time of the outermost transiting planet Kepler-51d recently measured by the James Webb Space Telescope (JWST) 10 years after the Kepler observations is significantly discrepant from the prediction made by the three-planet TTV model, which we confirmed with ground-based and follow-up HST observations. We show that the departure from the three-planet model is explained by including a fourth outer planet, Kepler-51e, in the TTV model. A wide range of masses ($\lesssim M_\mathrm{Jup}$) and orbital periods ($\lesssim 10\,\mathrm{yr}$) are possible for Kepler-51e. Nevertheless, all the coplanar solutions found from our brute-force search imply masses $\lesssim 10\,M_\oplus$ for the inner transiting planets. Thus their densities remain low, though with larger uncertainties than previously estimated. Unlike other possible solutions, the one in which Kepler-51e is around the $2:1$ mean motion resonance with Kepler-51d implies low orbital eccentricities ($\lesssim 0.05$) and comparable masses ($\sim 5\,M_\oplus$) for all four planets, as is seen in other compact multi-planet systems. This work demonstrates the importance of long-term follow-up of TTV systems for probing longer period planets in a system.
title A Fourth Planet in the Kepler-51 System Revealed by Transit Timing Variations
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2410.01625