Ephemeris refinement of 21 hot Jupiter exoplanets with high timing uncertainties^⋆

¹ Leibniz-Institut für Astrophysik Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany
e-mail: mmallonn@aip.de
² Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
³ Institut de Ciéncies de l’Espai (ICE, CSIC), Campus UAB, Carrer de Can Magrans s/n, 08193 Cerdanyola del Vallès, Spain
⁴ Institut d’Estudis Espacials de Catalunya (IEEC), C/Gran Capitá 2-4, Edif. Nexus 08034 Barcelona, Spain
⁵ Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque, B1900FWA La Plata, Argentina
⁶ Instituto de Astrofísica de La Plata (CCT-La Plata, CONICET-UNLP), Paseo del Bosque, B1900FWA La Plata, Argentina
⁷ Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA
⁸ Dept. of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
⁹ Center of Astro-Engineering UC, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago, Chile
¹⁰ Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, 7820436 Macul, Santiago, Chile
¹¹ Millennium Institute of Astrophysics, Av. Vicuña Mackenna 4860, 782-0436 Macul, Santiago, Chile
¹² Observatoire des Baronnies provencales, Observatoire Astronomique, 05150 Moydans, France
¹³ Observatory Puig d’Agulles, Carrer Riera 1, 08759 Vallirana, Spain
¹⁴ Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
¹⁵ NASA Goddard Space Flight Center, Exoplanets and Stellar Astrophysics Laboratory, Greenbelt, MD 20771, USA
¹⁶ Emory University Department of Physics, 400 Dowman Drive, Suite N218, Atlanta, GA 30322, USA
¹⁷ Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
¹⁸ Rarotonga Observatory, PO Box 876, Rarotonga, Cook Islands
¹⁹ La Vara, Valdes Observatory, 33784 Muñas de Arriba, Valdés, Asturias, Spain
²⁰ Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011, PR China
²¹ Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650216, PR China
²² University of Chinese Academy of Sciences, Beijing 100049, PR China
²³ Observatori Astronòmic Albanyà, Camí de Bassegoda s/n, 17733 Albanyà, Spain
²⁴ Observatoire Astronomique de Vaison, 84110 Vaison la Romaine, France
²⁵ National Youth Space Center, 59567 Goheung, Jeollanam-do, South Korea
²⁶ Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8042 Graz, Austria
²⁷ Anunaki Observatory, Calle de los Llanos, 28410 Manzanares el Real, Spain
²⁸ School of Physical Sciences, The Open University, Milton Keynes MK7 6AA, UK
²⁹ Gruppo Astrofili Salese “Galileo Galilei”, Via G. Ferraris 1, 30036 Santa Maria di Sala (VE), Italy
³⁰ Las Cumbres Observatory, 6740 Cortona Dr., Suite 102, Santa Barbara, CA 93117, USA
³¹ Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnij Arkhyz 369167, Russia
³² Central Astronomical Observatory at Pulkovo of Russian Academy of Sciences, Pulkovskoje shosse d. 65, St., Petersburg 196140, Russia

Received: 8 November 2018
Accepted: 14 December 2018

Abstract

Transit events of extrasolar planets offer a wealth of information for planetary characterization. However, for many known targets, the uncertainty of their predicted transit windows prohibits an accurate scheduling of follow-up observations. In this work, we refine the ephemerides of 21 hot Jupiter exoplanets with the largest timing uncertainties. We collected 120 professional and amateur transit light curves of the targets of interest, observed with a range of telescopes of 0.3 m–2.2 m, and analyzed them along with the timing information of the planets discovery papers. In the case of WASP-117b, we measured a timing deviation compared to the known ephemeris of about 3.5 h, and for HAT-P-29b and HAT-P-31b the deviation amounted to about 2 h and more. For all targets, the new ephemeris predicts transit timings with uncertainties of less than 6 min in the year 2018 and less than 13 min until 2025. Thus, our results allow for an accurate scheduling of follow-up observations in the next decade.