Eclipse mapping with Ariel : future prospects for a population-level mapping survey

Monthly Notices of the Royal Astronomical Society, vol. 544, pp. 3647–3682

Abstract

ABSTRACT Eclipse mapping is a powerful tool for measuring 3D profiles of exoplanet atmospheres. To date, only JWST has been capable of widely applying this technique, but as a general observatory, it is too time-limited to conduct population-level mapping studies. Ariel, on the other hand, is a dedicated exoplanet mission set to observe 1000 transiting exoplanets, making it a natural candidate for this. To assess Ariel’s mapping potential, we quantitatively benchmark its abilities against those of JWST using a simulation-and-retrieval framework with existing JWST eclipse maps as test cases. We find that for high-ranking targets, Ariel will be able to derive qualitatively similar maps to JWST using the same amount of observations; for mid-ranking targets, Ariel will be able to compete using as few as 3$\times$ as many observations; and for lower ranking targets, the use of phase curves overcomes the need for an impractical number of repeated eclipse observations. We find that while Ariel is unlikely to have extensive latitudinal mapping abilities, it will have wide-ranging longitudinal abilities, from which the first-order atmospheric dynamics can be constrained. Using an analytically derived metric, we determine the best eclipse mapping targets for Ariel, finding that it will be able to map nearly 100 targets using full phase curves in only quarter of its lifetime. This would be the largest mapping survey to date, and have enormous ramifications for our understanding of exoplanet atmospheric dynamics. Finally, we rank all the best mapping targets for both JWST and Ariel in order to encourage future eclipse mapping studies.

Authors 6

1. Hannah R. Wakeford

   University of Bristol

   Affiliation as printed

   School of Physics, University of Bristol , HH Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL ,

   School of Physics, University of Bristol, HH Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL, UK

2. Mark Hammond

   University of Oxford

   Affiliation as printed

   University of Oxford Department of Physics, , Oxford OX1 3PU ,

   Department of Physics, University of Oxford, Oxford OX1 3PU, UK

3. Ryan C. Challener

   Cornell University

   Affiliation as printed

   Cornell University Department of Astronomy, , 122 Sciences Drive, Ithaca, NY 14853 ,

   Department of Astronomy, Cornell University, 122 Sciences Drive, Ithaca, NY 14853, USA

4. Billy Edwards Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research , Niels Bohrweg 4, NL-2333 CA Leiden ,

   SRON Netherlands Institute for Space Research , Niels Bohrweg 4, 2333 CA Leiden, Netherlands

5. T. Lüftinger

   European Space Agency · European Space Research and Technology Centre

   Affiliation as printed

   European Space Agency (ESA), European Space Research and Technology Centre (ESTEC) , Keplerlaan 1, NL-2201 AZ Noordwijk ,

   European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands

6. Maximilian N. Günther

   European Space Agency · European Space Research and Technology Centre

   Affiliation as printed

   European Space Agency (ESA), European Space Research and Technology Centre (ESTEC) , Keplerlaan 1, NL-2201 AZ Noordwijk ,

   European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands