John Hugh Seiradakis — Greek radio astronomer and archaeoastronomer

Overview of research and interests

Seiradakis made sustained contributions to observational radio astronomy, particularly in studies of pulsars and related timing techniques that probe neutron star physics and the interstellar medium. He also investigated radio emission from the region around the Milky Way’s centre, bringing radio techniques to bear on questions about compact sources and their environments. In parallel, he pursued archaeoastronomy, examining how ancient societies observed and recorded celestial phenomena and how that knowledge is encoded in surviving monuments.

Career and institutional affiliations

During his career Seiradakis held positions at several universities and research institutes. These included the University of Thessaloniki and international centres such as the Max Planck Institute for Radio Astronomy and the University of Hamburg. He spent periods working within the University of California system (University of California) and at the Victoria University of Manchester, contributing to collaborative projects that linked European and American radio facilities.

Community roles and foundations

Beyond research, he helped build the professional infrastructure of astronomy in Greece and Europe. He was a founding member of the Hellenic Astronomical Society and a founder of the European Astronomical Society. He also helped establish the International Olympiad on Astronomy and Astrophysics (IOAA), an event that promotes astronomy education for talented secondary-school students worldwide.

Selected themes and impact

• Pulsar studies: observational timing and radio techniques that inform models of neutron stars.
• Galactic Centre research: radio observations addressing the nature of compact and diffuse emission near the Milky Way’s nucleus.
• Archaeoastronomy: comparative study of ancient observational practices and monument alignments.

Colleagues remember Seiradakis for his combination of observational skill and interest in cultural astronomy, bringing interdisciplinary perspectives to both modern astrophysics and the study of historical sky knowledge.

Death and legacy

John Hugh Seiradakis died on 3 May 2020 at his home in Thessaloniki, Greece, after an illness related to cancer. He was 72. His legacy includes his published research, the societies he helped found, and the generations of students and colleagues influenced by his work.

For more information about his publications and professional activities, see institutional pages and obituaries from astronomical societies and research centres (details and tributes).