Editorial: The Future of Asteroseismology

Abstract

Rapid progress in the field of asteroseismology continues to be propelled by data from space missions. Since the time that this special topic was proposed in early 2017, the NASA Kepler/K2 missions have ended (November 2018) and the Canadian MOST spacecraft was decommissioned (March 2019). In April 2018, the NASA TESS mission was launched, and has collected data on nearly all of the sky both north and south of the ecliptic plane. The BRITE Constellation satellites (Austria-Poland-Canada) continue operation, and a new European Space Agency mission, PLATO, is planned for launch in 2026. In addition, during this period the Gaia mission Data Release 2 (Gaia Collaboration et al., 2018) has providedmore accurate parallaxes for over one billion stars, hence constraints on distance and luminosity for asteroseismic models. The ESA/Swiss Space Office CHEOPS space telescope was launched in December 2019 (Fortier et al., 2014). Its mission is to measure sizes of known transiting exoplanets orbiting bright and nearby stars, but it will also have significant capability for asteroseismology, collecting high-cadence photometry with precision similar to that of Kepler and TESS (Moya et al., 2018). Our original objectives for this topical issue are outlined in the “About This Research Topic” preface to the collection.While we had hoped for as many as 50 contributions, in the end 18 excellent and very diverse papers have been published: four Perspective articles, a two-part Methods article, four Reviews, two Mini-Reviews, and six Original Contributions. We asked the authors to consider articles that were “speculative and even controversial.” We encouraged reviewers to be open-minded about predictions, opinions, and conclusions that differed frommainstream views.We hoped that this collection would become a resource for research advisors and students to inspire new projects and directions. Of the twelve suggested topics listed in the preface, the eighteen articles address directly or indirectly all but three of them. The exceptions are connections to related fields, such as supernovae progenitors, and seismology of planets and circumstellar disks. A notable omission is discussion of asteroseismology of stars in binary and multiple star systems, despite the increasing literature in this area. This absence highlights the difficulty of taking into account the effects of close binary companions in stellar evolution and pulsation models, which is usually done in an approximate way, and points to an area where advances are needed. We recommend the recent review of asteroseismology in close binary systems by Zhao Guo in the Frontiers Research Topic Asteroseismology in the Kepler Era. This latter collection also contains articles on asteroseismology for variable star types that were not addressed specifically in the present collection, such as white dwarfs (Córsico, 2020), hot subdwarfs (Lynas-Gray, 2021), high-mass stars (Bowman, 2020), and RR Lyrae variables (Plachy and Szabó, 2021). Edited by: Scott William McIntosh, National Center for Atmospheric Research (UCAR), United States