Summer 2021, Toulouse, France

The "Cambridge Workshops of Cool Stars, Stellar Systems and the Sun" are held biennially and have evolved to be the premier conference series for cool star research.

Dear Colleagues,

We regret to announce that the Cool Stars, Stellar Systems, and the Sun 21st Conference, originally planned to be held on June 22-26, 2020, in Toulouse, France, has to be postponed due to the current Covid-19 pandemic. The decision was discussed within the SOC and LOC, and agreed by all members of the organizing committees. We plan to reschedule CS21 in Summer 2021.

Preliminary dates (tbc) for CS21 would be 5-9 July 2021, at the same location in Toulouse, France. We foresee that the program that was designed for CS21 this year, including the planned invited talks and the scheduled splinter sessions, will still be largely relevant next year, unless other hot topics emerge till then. We will continue to provide updated information on the current CS21 website.

As chairs of the SOC and LOC, we would like to express our gratitude to all the members of the organizing committees, especially to the members of the LOC for the efforts they deployed in this uncertain context. We extend our thanks to the chairs of the proposed Splinter sessions, to the speakers who accepted our invitation for the plenary sessions, and to all of you who had registered for the conference.

Take care, and we hope to see you next year!

S. Brun, J. Bouvier, P. Petit

What is "Cool Stars"?

The next edition of the conference series "Cool Stars, Stellar Systems and the Sun" (CS 21) will be held in Toulouse in 2021, about 40 years after its first edition in Cambridge (USA). This first edition was shortly followed that same year by a workshop on "Solar Phenomena in Stars and Stellar Systems" that took place in the southern French countryside, in a small village called Bonas. Both meetings are often considered as the starting point of this exceptionally successful conference series, where approximately 400 international experts in Low-Mass Stars, Solar Physics, and Exoplanets meet every other year to exchange ideas in a cross-disciplinary and friendly environment. Bonas is certainly not adapted anymore to host what became a major conference, but we will have CS 21 a stone throw away from there in Toulouse, where attendees will enjoy a certain lifestyle that - fortunately - has not change over the last forty years!


To contact the SOC or LOC write to:

  • Silvia Alencar - Federal University of Minas Gerais
  • Myriam Benisty - Institut de Planétologie et d'Astrophysique de Grenoble
  • Jérôme Bouvier (SOC co-chair) - Institut de Planétologie et d'Astrophysique de Grenoble
  • Allan Sacha Brun (SOC chair) - CEA Saclay
  • Corinne Charbonnel - Geneva Observatory
  • Marc DeRosa - Lockheed Martin Solar and Astrophysics Laboratory
  • Andrea Dupree - Harvard-Smithsonian Center for Astrophysics
  • Luca Fossati - Austrian Academy of Sciences
  • Laurent Gizon - Max Planck Institute for Solar System Research
  • Gregory Herczeg - KIAA / Peking University
  • Lynne Hillenbrand - California Institute of Technology
  • Miho Janvier - IAS / University of Paris-Sud
  • Moira Jardine - University of Saint Andrews
  • Carme Jordi - University of Barcelona
  • Elena Khomenko - Instituto de Astrofísica de Canarias
  • Heidi Korhonen - European Southern Observatory
  • Ágnes Kóspál - Konkoly Observatory
  • Sean Matt - University of Exeter
  • Pascal Petit (LOC chair) - Institut de Recherche en Astrophysique et Planétologie
  • Sofia Randich - INAF / Arcetri Astrophysical Observatory
  • Rachael Roettenbacher - Yale University
  • Alexis Rouillard - Institut de Recherche en Astrophysique et Planétologie
  • Klaus Strassmeier - Leibniz-Institut für Astrophysik Potsdam
  • Takeru Suzuki - University of Tokyo
  • Adriana Valio - Mackenzie Presbyterian University
  • Scott Wolk - Harvard-Smithsonian Center for Astrophysics


To contact the SOC or LOC write to:

  • Jérôme Ballot - Institut de Recherche en Astrophysique et Planétologie (IRAP)
  • Clément Baruteau - IRAP
  • Anaïs Bertranuc - Insight Outside
  • Florian Debras - IRAP
  • Sébastien Deheuvels - IRAP
  • Dolorès Granat - IRAP
  • Léa Griton - IRAP
  • Laurène Jouve - IRAP
  • Soizic Peron - Insight Outside
  • Pascal Petit (LOC chair) - IRAP
  • Nicolas Poirier - IRAP
  • Victor Reville - IRAP
  • Alexis Rouillard - IRAP

Organizing Institutions



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