Prof. Riccardo Giacconi

ESO’s Director General from 1993 to 1999

Riccardo GiacconiBorn on 6 October 1931 in Genoa, Italy, Giacconi spent most of his young life in Milan, where he obtained a degree in Physics from the University of Milan. Although he didn’t enjoy lectures, he discovered a love for practical scientific research. Giacconi carried out his thesis on the development of nuclear interactions by protons in the lead plates of a cloud chamber, completing his PhD in 1954. While carrying out this research he met Giuseppe Occhialini, a physicist who suggested that Giacconi travel to the United States to work with the experimental physicist R. W. Thompson.

In 1956 Giacconi won a scholarship through the Fulbright Program, which enabled him to immigrate to the United States and work on the analysis of data previously obtained by Thompson at Indiana University. Two years later a fellowship position at Princeton University allowed him to work in G. Reynolds’ laboratory from 1958 to 1959. There he conducted research into mesons and carried out an unsuccessful search for a new type of particle.

During his research, Giacconi was at the forefront of developing and applying X-ray technologies to astronomy, which led to the first discovery of an extrasolar X-ray source. This work, he believes, started in 1959 when he received an offer from American Science & Engineering (AS&E) — an X-ray technology supplier — to initiate a space science program for the corporation. He decided that the program should focus on astronomy at X-ray wavelengths, a decision that effectively marked the beginning of X-ray astronomy. Giacconi and his team at AS&E began the initial development of X-ray telescopes, and he was involved in a great deal of exciting research including development of a satellite and payloads for rockets, satellites, and aircraft. After discovering Scorpius X-1 in 1962, the first known X-ray source outside the solar system, Giacconi’s group launched the first X-ray satellite, Uhuru, in 1970.

Following Uhuru’s success, Giacconi’s team won the contract to build the Large Orbiting X-ray Observatory for NASA, which was eventually cancelled and replaced the same year with the Einstein Observatory (HEAO-2). Giacconi’s group moved to Harvard to develop this new X-ray telescope, which was launched in 1978. Two years before Einstein was even launched, Giacconi proposed to NASA an X-ray astronomy institute to direct the construction and operation of Einstein’s successor, the Chandra X-ray Observatory. It was not until almost twenty years later that Chandra was launched.

Giacconi became director of the Space Telescope Science Institute (STScI) when it was established in Baltimore in 1981, where he oversaw the planning and execution of Hubble Space Telescope science operations. Simultaneously, he held a professorship at the Johns Hopkins University, and more recently, on a part-time basis, at the University of Milan. The STScI has been central to the Hubble's success and serves a worldwide community of users.

In 1993 Giacconi became ESO’s Director General, just as ESO was beginning to execute the extremely ambitious Very Large Telescope (VLT) programme.

During his time at ESO, Giacconi fully reorganised the organisation to introduce modern management techniques suitable for large programmes. The reorganisation established delegation of accountability and responsibility to appropriate staff members and kindled more collaboration between staff in Chile and Germany.

Giacconi’s tenure at ESO also saw many developments on existing and new telescopes. Funds for La Silla were redistributed toward supporting the most productive telescopes, including new hardware for the New Technology Telescope (NTT). Under Giacconi, the VLT overcame significant technological and financial difficulties, and two of the Unit Telescopes saw first light toward the end of his term. At the same time, Giacconi initiated ESO’s involvement in another ambitious project: the Atacama Large Millimeter/submillimeter Array (ALMA).

Upon leaving ESO, Giacconi returned to the United States to take up a post as President of Associated Universities Incorporated (AUI) in 2002.

Giacconi was also awarded a share of the Nobel Prize in Physics in 2002 for “pioneering contributions to astrophysics, which have led to the discovery of cosmic X-ray sources”.

Giacconi was married and had two children. He died on 9 December 2018 at the age of 87.

A detailed CV is below.

Prof. Riccardo Giacconi

Born in Genoa, Italy in 1931; Italian nationality.


PhD in Physics, University of Milan, Milan, Italy (1954)

Degree in Physics, University of Milan, Milan, Italy

Professional Activities:

  • 1954–1956: Assistant Professor of Physics, University of Milan, Italy
  • 1956–1958: Research Associate (Fulbright Fellow), Indiana University, USA
  • 1958–1959: Research Associate, Princeton University, USA
  • 1959–1973: Senior Scientists, American Science and Engineering, USA
  • 1966–1973: Member of the Board of Directors, American Science and Engineering, USA
  • 1969–1973: Executive Vice President, American Science and Engineering, USA
  • 1973–1982: Professor, Harvard University, USA
  • 1973–1981: Associate Director, Harvard-Smithsonian Center for Astrophysics, USA
  • 1981–1992: Director, Space Telescope Science Institute (STSci), USA
  • 1981–1999: Professor, Johns Hopkins University, USA
  • 1993–1999: Director General, European Southern Observatory, Germany
  • 1999–Present: Research Professor, Johns Hopkins University, USA
  • 2000–2004: President, Associated Universities Inc., USA

Research: Cosmic rays, X-rays astronomy, optical astronomy

Publications: (Co)-authored 400 publications; authored or co-edited four books


  • International Astronomical Union
  • American Astronomical Society
  • National Academy of Sciences
  • American Academy of Arts and Sciences
  • Accademia Nazionale dei Lincei
  • The Royal Astronomical Institute
  • Max-Planck Society
  • American Physical Society
  • American Association for the Advancement of Science
  • Istituto Lombardo–Accademia delle Scienze e Lettere

Other Affiliations and Honours:

  • Fulbright Fellow, 1956–1958
  • Helen B. Warner Prize for Astronomy, American Astronomical Society, 1966
  • Röntgen Prize in Astrophysics for 1971, Physikalisch-Medizinische Gesellschaft, 1971
  • NASA Medal for Exceptional Scientific Achievement, 1971
  • NASA Distinguished Public Service Award, 1972
  • Richtmeyer Memorial Lecture Award, American Association of Physics Teachers, 1975
  • Elliott Cresson Medal, the Franklin Institute, 1980
  • Catherine Wolfe Bruce Gold Medal, Astronomical Society of the Pacific, 1981
  • Henry Norris Russell Lectureship, American astronomical Society, 1981
  • Dannie Heineman Prize for Astrophysics, American Institute of Physics and American Astronomical Society, 1981
  • Gold Medal of the Royal Astronomical Society, the Royal Astronomical Society, 1982
  • The A. Cressy Morrison Award in Natural Sciences, The New York Academy of Sciences, 1982
  • Honorary Doctor of Science, The University of Chicago, 1983
  • Laurea Honoris Causa in Astronomia, The University of Padua, 1984
  • Wolf Foundation Prize in Physics, Wolf Foundation, 1987
  • Honorary Doctor of Science, University of Warsaw, 1996
  • Laurea Honoris Causa in Physics, University of Rome, 1998
  • Honorary Doctor of Technology and Science, University of Uppsala, Sweden, 2000
  • Marcel Grossmann Award, International Center for Relativistic Astrophysics, 2000
  • Nobel Prize in Physics, Royal Swedish Academy of Sciences, 2002
  • President’s National Medal of Science, President of the United States, 2003
  • Cavaliere di Gran Croce Ordine al Merito della Repubblica Italiana, 2003
  • Karl Schwarzschild Medal, Astronomische Gesellschaft, 2004
  • Laurea Honoris Causa, University of Chile, 2004
  • Laurea Honoris Causa, University Paul Sabatier, Toulouse, France, 2004
  • Asteroid 3371 Giacconi is named after him