Dr. Catherine Cesarsky

ESO Director General from 1999 until 2007

Catherine Cesarsky

Born in France, Catherine Cesarsky received a degree in Physical Sciences at the University of Buenos Aires and graduated with a PhD in Astronomy in 1971 from Harvard University (Cambridge, Mass., USA). She worked at the California Institute of Technology. In 1974, she moved to France, becoming a staff member of the Service d'Astrophysique (SAp), Direction des Sciences de la Matière (DSM), Commissariat à l'Energie Atomique (CEA). She then established her career in France. From 1985 to 1993, she was the Head of SAp. Later, as Director of DSM (1994–1999), she led a team of about 3000 scientists, engineers and technicians active within a broad spectrum of basic research programmes in physics, chemistry, astrophysics and earth sciences. From 1999 to 2007, she was the Director General of the European Southern Observatory. From 2009 to 2012, she was High Commissioner for Atomic Energy in France, advisor to the French government for science and energy issues. Now, she is High level Science Advisor at CEA.

Catherine Cesarsky’s research activities span several areas of modern astrophysics. The first part of her career was devoted to the high-energy domain. This has involved studies of the propagation and composition of galactic cosmic rays, of matter and fields in the diffuse interstellar medium, as well as the acceleration of particles in astrophysical shocks, e.g. in connection with supernovae.

She then turned to infrared astronomy. She was the Principal Investigator of the ISOCAM camera onboard the Infrared Space Observatory (ISO) of the European Space Agency (ESA), which flew between 1995 and 1998. As such, she has lead the ISOCAM central programme, which studied, in a coordinated way, the infrared emission from a variety of galactic and extragalactic sources and yielded new and exciting results on star formation and galactic evolution. These were consolidated through further observations with the ESO VLT, the satellites Spitzer and Herschel.

From August 2006 to August 2009, Catherine Cesarsky was President of the International Astronomical Union. She is recipient of the 1998 COSPAR (Committee on Space Research) Space Science Award, and member or foreign member of various Academies (French Académie des Sciences, Academia Europaea, International Academy of Astronautics, National Academy of Sciences USA, Royal Swedish Academy of Sciences, Royal Society of London) and holds a Honoris Causa Doctorate from the University of Geneva. She is Commandeur de l’Ordre National du Mérite and Commandeur de l’Ordre la Légion d’Honneur.

A detailed CV is below.

Dr. Catherine Cesarsky

Born in Ambazac, France.
Married, two children.


  • 19591965: Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Licenciada en Ciencias Fisicas
  • 19661971: Harvard University, Cambridge, Mass. PhD in Astronomy

University fellowships and assistantships

  • 19611963: Ayudante de 2a en Fisica, Universidad de Buenos Aires
  • 19631965: Beca del Consejo Nacional de Investigaciones Cientificas y Tecnicas
  • 19661970: Teaching Fellow at Harvard University:
    • 19661967: Pickering Fellowship
    • 19681969: Harvard Scholarship
    • 19691970: Pickering Fellowship
  • 19701971: M. Weyerhaeuser Jewett Research Fellowship

Professional Activities

  • 19651966: Instituto Argentino de Radioastronomia, Research Fellow
  • 19711974: California Institute of Technology, Astronomy Department, Research Fellow
  • 19741978: Staff member of the Service d'Astrophysique (Sap), Direction des Sciences de la Matière (DSM), CEA Saclay
  • 19781985: Head of the theoretical group of the SAp
  • 19851993: Head of the SAp
  • 19941999: Director of DSM
  • 19992007: Director General of ESO
  • 2006-2009: she was President of the International Astronomical Union (IAU)
  • 2007-present: High Scientific Advisor to the General Administrator, CEA
  • 20092012: High Commissioner for Atomic Energy, CEA Saclay
  • 2017-2021: Chairman of the Board of the Square Kilometre Array (SKA) Organisation
  • 2021-present: Chair of the SKA Observatory Council

Sabbatical Leaves

  • May 1976: Institute of Astronomy, Cambridge
  • May 1977: Weisman Institute, Israel
  • MayJune 1978: University of Chicago
  • Nov. 1981: ESO, Garching
  • Summers 1982 and 1989: University of California at Berkeley

Main Scientific Results

  • Theoretical work on the propagation of galactic cosmic rays and their resonant interactions with hydromagnetic waves. Proponent of the energy dependent leaky-box model for galactic propagation; connection with interstellar turbulence and with the heating of the interstellar medium
  • Studies and observations of radio recombination lines from the diffuse interstellar medium; the role of cold regions
  • Determination of the column of interstellar matter to the galactic center through studies of X-ray absorption
  • Interpretation of results on cosmic ray composition: implications for the origin and the propagation of these particles
  • Diffuse gamma ray emission: a new measure of the density of the interstellar gas and of the spectrum of low energy cosmic ray electrons. Penetration of cosmic rays in molecular clouds
  • Parker instability: Demonstration that curved equilibria of the cosmic ray, magnetic field and interstellar gas system, linked by flux conservation to unstable horizontal equilibria, are also unstable. Establishment of a stability criterion applicable to all type of horizontal equilibria
  • Particle acceleration in astrophysical shocks. In particular, establishment of an upper limit for the energy that cosmic rays can gain from the interaction with a supernova shock. Proponent of stellar winds of WR stars as accelerators of cosmic rays in the 1015 GeV range. Re-acceleration of cosmic rays in the interstellar medium. The problem of the highest energy cosmic rays; role of galaxy collisions
  • Coordination of the ISOCAM Central Programme: infrared emission from the diffuse interstellar medium, dust formation in supernovae, infrared emission from high energy sources, star formation in molecular clouds and in galaxies, etc.
  • Principal Investigator of the ITGES collaboration, which conducted deep surveys with ISOCAM. These deep surveys revealed a population of Luminous Infrared Galaxies with median redshift ~ 0.8, which are responsible for the bulk of the energy in the Cosmic Infrared Background. Follow-up studies of these objects with various telescopes, including VLT and HST are on going.

Publications: Author of more than 350 scientific papers.

Space Experiments

  • Co-Investigator of
    • GOLF on SOHO
    • EPIC on XMM
  • Scientific associate of ISGRI, on INTEGRAL
  • Principal Investigator of ISOCAM on ISO
  • Scientific associate of HFI on PLANCK

Some Other Activities Related To Scientific Research

  • 19771980: Member of the Astronomy Working Group at the European Space Agency
  • 19801983: Chair of the Astronomy and Astrophysics Division of the European Physical Society
  • 19821985: Editor in Chief of the Journal Astronomy and Astrophysics
  • 19851988: President of IAU Commission no 48: High Energy Astrophysics
  • 19921993: Chair of the Observing Programme Committee of the European Southern Observatory
  • 19931994: Vice Chair of the ESO Council
  • 19941996: Member of the Conseil Supérieur de la Recherche et de la Technologie, French Ministry of Research
  • 19941996: President of the French Society of Professional Astronomers
  • 19931997: Vice President of the European Astronomical Society
  • 19972003: Vice President of the International Astronomical Union
  • 20012004: Member of the board of the European Research Advisory Board
  • 2002Present: Honorary Member of the American Astronomical Society
  • 20032006: President Elect of the International Astronomical Union
  • 2004Present: Member of the European Research Advisory Board
  • 2005Present: President of the Comité des Programmes Scientifiques du Cnes (Centre National d'Etudes Spatiales)
  • 20062009: President of the International Astronomical Union

She also contributed in 1994 to a report on the main objectives of research in France for the French Ministry of Research. In the framework of the "Consultation Nationale" conducted by the Minister of Research François Fillon, she chaired the Bordeaux colloquium: Recherche fondamentale: conforter les atouts de la France.

C. Cesarsky is or has been a member of the Visiting Committees of Harvard College Observatory, Space Telescope Science Institute, and the European Southern Observatory. She also participates in, has participated in, or chaired the Haut Comité de l'Observatoire de Paris, the Fachbeirat of the Max Planck Institut für Kernphysik (Heidelberg), the Max Planck Institut für Astrophysik (Garching), the Max Planck Insitut für Extraterrestrische Physik (Garching), the Max Planck Institut für Radioastronomie (Bonn) and ESRON (Netherlands). She is a member of the Academia Europaea, of the European Academy of Sciences, and of the International Academy of Astronautics. She is a Foreign Associate of the National Academy of Sciences of the United States of America, a Foreign Member of the Royal Swedish Academy of Sciences and a Foreign Member of the Royal Society of London.


  • COSPAR Space Science Award 1998
  • Prix Jules Janssen of the Société astronomique de France (French Astronomical Society) (2009)
  • 2020 Tate medal assigned by American Institute of Physics every two years to non-US citizens for their leadership


  • Chevalier de l'Ordre National du Mérite (1989)
  • Chevalier de la Légion d'Honneur (1994)
  • Officier de l'Ordre National du Mérite (1999)
  • Officier de la Légion d'Honneur (2004)
  • Foreign Member of the Royal Society of London (2005)
  • Foreign Associate of the National Academy of Sciences of the United States of America (2005)
  • Member of the French Academy of Sciences (2007)
  • Commandeur de l'Ordre national du Mérite (2008)
  • 2010 Doctorate Honoris Causa University of Geneva
  • Commandeur de la Légion d'Honneur (2011)
  • Grand Officier de la Légion d'Honneur (2018)
  • Member of the Academia Europaea
  • Member of the International Academy of Astronautics
  • Foreign Member of the Royal Swedish Academy of Sciences