Sean G. Ryan is a professional astronomer with fifty years’ experience as an amateur observer. As a teenager, he learnt his craft observing with a 16 inch Newtonian telescope at his local astronomical society, largely under the mentorship of David Buckley who later became Project Scientist for the Southern African Large Telescope. While studying astronomy, physics and mathematics at the University of Canterbury, NZ, Sean operated the University's 6 inch refractor at weekly public nights. He undertook a PhD at the Mount Stromlo and Siding Spring Observatories, researching the composition and motions of the oldest stars in the Galaxy, supervised by Professor John Norris, observing extensively with 1 metre, 74 inch, 2.3 m and 3.9 m telescopes. Following his PhD, he worked at the University of Victoria, BC, and in 1991 was awarded a Hubble Fellowship at the University of Texas. Staff posts at the Anglo-Australian Observatory and the Royal Greenwich Observatory followed later, including a five month secondment to the National Astronomical Observatory of Japan. In 1999, Sean took up an academic post at the Open University, UK. He was appointed Professor of Astrophysics at the University of Hertfordshire in 2006, and held the post of Head and Dean of the School of Physics, Astronomy and Mathematics for ten years. He developed the University's optics course for trainee optometrists, and expanded his research into microscopy and biomedical imaging. He has observed on countless nights at a wide range of northern and southern hemisphere observatories, has published over 100 research papers on observational astronomy, and has co-authored several textbooks.
