ExoClock Project: An open platform for monitoring the ephemerides of Ariel targets with contributions from the public
Creators: name: Kokori, Anastasia
name: Tsiaras, Angelos
name: Edwards, Billy
name: Rocchetto, Marco
name: Tinetti, Giovanna
name: Wünsche, Anaël
name: Paschalis, Nikolaos
name: Agnihotri, Vikrant Kumar
name: Bachschmidt, Matthieu
name: Bretton, Marc
name: Caines, Hamish
name: Caló, Mauro
name: Casali, Roland
name: Crow, Martin
name: Dawes, Simon
name: Deldem, Marc
name: Deligeorgopoulos, Dimitrios
name: Dymock, Roger
name: Evans, Phil
name: Falco, Carmelo
name: Ferratfiat, Stephane
name: Fowler, Martin
name: Futcher, Stephen
name: Guerra, Pere
name: Hurter, Francois
name: Jones, Adrian
name: Kang, Wonseok
name: Kim, Taewoo
name: Lee, Richard
name: Lopresti, Claudio
name: Marino, Antonio
name: Mallonn, Matthias
name: Mortari, Fabio
name: Morvan, Mario
name: Mugnai, Lorenzo V.
name: Nastasi, Alessandro
name: Perroud, Valère
name: Pereira, Cédric
name: Phillips, Mark
name: Pintr, Pavel
name: Raetz, Manfred
name: Regembal, Francois
name: Savage, John
name: Sedita, Danilo
name: Sioulas, Nick
name: Strikis, Iakovos
name: Thurston, Geoffrey
name: Tomacelli, Andrea
name: Tomatis, Alberto
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The Ariel mission will observe spectroscopically around 1000 exoplanets to further characterise their atmospheres. For the mission to be as efficient as possible, a good knowledge of the planets' ephemerides is needed before its launch in 2028. While ephemerides for some planets are being refined on a per-case basis, an organised effort to collectively verify or update them when necessary does not exist. In this study, we introduce the ExoClock project, an open, integrated and interactive platform with the purpose of producing a confirmed list of ephemerides for the planets that will be observed by Ariel. The project has been developed in a manner to make the best use of all available resources: observations reported in the literature, observations from space instruments and, mainly, observations from ground-based telescopes, including both professional and amateur observatories. To facilitate inexperienced observers and at the same time achieve homogeneity in the results, we created data collection and validation protocols, educational material and easy to use interfaces, open to everyone. ExoClock was launched in September 2019 and now counts over 140 participants from more than 15 countries around the world. In this release, we report the results of observations obtained until the 15h of April 2020 for 119 Ariel candidate targets. In total, 632 observations were used to either verify or update the ephemerides of 83 planets. Additionally, we developed the Exoplanet Characterisation Catalogue (ECC), a catalogue built in a consistent way to assist the ephemeris refinement process. So far, the collaborative open framework of the ExoClock project has proven to be highly efficient in coordinating scientific efforts involving diverse audiences. Therefore, we believe that it is a paradigm that can be applied in the future for other research purposes, too.
description: 33 pages, 3 figures, 3 tables, accepted for publication in Experimental Astronomy, data available through OSF at DOI: 10.17605/OSF.IO/3W7HM