This year, the Shaw Prize in Astronomy has been awarded to Michael Perryman, Adjunct Professor, UCD School of Physics, University College Dublin, for his lifetime contributions to space astrometry, and in particular for his role in the conception and design of the European Space Agency’s Hipparcos and Gaia missions. The prize was awarded jointly to Professor Perryman and Lennart Lindegren, Professor Emeritus, Department of Astronomy and Theoretical Physics, Lund Observatory, Lund University, Sweden.
The Shaw Prize honours individuals who are currently active in their respective fields and who have achieved significant breakthroughs in academic and scientific research or applications, and whose works have resulted in a positive and profound impact on mankind.
Launched in August 1989, ESA's Hipparcos space astrometry mission was a pioneering European project which pinpointed the positions of more than one hundred thousand stars with high precision, and more than one million stars with lesser precision. Gaia is an ambitious mission to chart a three-dimensional map of our galaxy, the Milky Way, in the process revealing the composition, formation and evolution of the galaxy.
Ahead of the prestigious annual Shaw Prize Lecture, we caught up with Professor Perryman to get a glimpse into the life of an award-winning astrometrist.
Why focus on astrometry?
I left Cambridge University in 1979 with a degree in mathematics and theoretical physics, and a PhD in radio astronomy. I was a research fellow with the European Space Agency in 1980 when the Hipparcos space astrometry project was selected by ESA, and they were looking for someone to be in charge of the scientific aspects of the mission. My Division Head at the time, Brian Fitton, suggested I look at the project to see if it held any interest. I knew almost nothing about astrometry then, but I could see the scientific importance of this new space discipline, and I was intrigued and excited by the clever mathematical basis of the proposed measurements. It was the prospect of making new advances in understanding the stars, and our Galaxy, and the novelty of the measurement technique, that drew me in.
Who has most inspired you in your career?
I learned a lot from many people during my career, but I don’t think I ever had a particular role model. My mathematics teacher at school in King’s Lynn around 1970, Harry Thornton, greatly stimulated my interest in mathematics, which has always been with me since. During my PhD studies, the head of department was Astronomer Royal and Nobel Prize laureate Martin Ryle, and I could see how he had developed a new scientific discipline from ongoing advances in technology. And, even then, I was impressed how he would visit the offices of we junior researchers, and show an interest in what we were doing. At ESA, I watched and learned from many experienced project managers, starting with Franco Emiliani who was the first project manager for Hipparcos. Inspiration continued with the many scientists and industrial leaders that I worked with throughout the Hipparcos and Gaia projects.
What do you enjoy most in your spare time?
Caving (going down holes in the ground) has been lifelong passion. The trips I do today are less technical and physical than in my youth but I still enjoy the astonishing beauty, the tranquility, and the physical challenge. Today I focus on caves of the Mendip Hills and South Wales, but other classics have been in Yorkshire, Derbyshire, the Pyrenees, Austria – and the Burren in Co. Clare.
It is a great pity that we seem unable to communicate to the world’s leaders and politicians how special Earth is, how delicate its equilibrium, how rich its diversity, and how easily this all might be lost, permanently and forever.
Space missions are big collaborations – what are the biggest challenges they posed?
I have long been fascinated by the conditions that exist in our society today that allows these big scientific undertakings to exist in the first place, and how considerable dedication from large numbers of astronomers, physicists, engineers, computer scientists, and policy makers is required to make them happen. Setting clear goals, actions and lines of responsibility, consulting widely, and making timely decisions are all key ingredients in making them happen. People get swept along and motivated by the collective vision. But keeping track of ongoing tasks, understanding compromises between scientific visions and technical feasibility, and setting clear and intermediate goals are always challenging. Today, more than 400 scientists are involved in producing the successive Gaia star catalogues. It really is a remarkable scientific collaboration.
What do you consider the ‘biggest moment’ of your career?
Let me pick out one highlight from some of the biggest scientific efforts that I was involved with during my 35-year career. For the Hipparcos project, I’ll go for the international conference held in Venice in 1997 to mark the release of the Hipparcos star catalogue to the world’s astronomers. A 17-year journey of designing, building, and operating the satellite led to this wonderfully successful catalogue, and the appreciation of the astronomers around the world. We had been working on the design of the follow-on Gaia mission in parallel with the completion of Hipparcos, and the next big moment came in 2000, when the Gaia project was selected by ESA as its next major astronomy mission. This was, again, the culmination of a huge scientific and technical effort in preparing the mission’s foundations.
I’ll add two other highlights. The first was in 1996 when my ideas for the detection of individual optical photons using superconducting tunnelling junctions led to the first experimental detection – and a paper in Nature. The other was the publication of my second edition of The Exoplanet Handbook in 2018. This was printed by the company TJ International (Padstow, Cornwall), and through some fortuitous circumstances, I was invited to see the first bound copies coming off the production line. The company treated me like a VIP but I was completely fascinated by their impressive industrial operation!
What’s your favourite book?
I read quite a lot, largely because my wife Julia is a voracious reader, and she passes on to me plenty of books that she thinks I should read. Amongst some recent favourites have been the Matthew Shardlake series of historical crime novels by C.J. Sansom, those set in ancient Rome by Robert Harris, the spy fiction novels of Charles Cumming, and the delightful novels of Amor Towles. But for my favourite, I’ll plump for the only book I’ve ever read three times, the non-fictional Journey Through Britain by John Hillaby. Written back in the 1960s, it is a delightful account of his solo walk from Land's End to John o' Groats.
Do you have a favourite astronomical object or body?
Yes, our own planet, Earth. The more we learn about our solar system, the more complex and bewildering it appears, and the more remarkable it seems that the conditions suitable for life to take hold and flourish emerged here. I think the majority of astronomers really do appreciate how special, and almost certainly how rare, are these conditions for the very long evolutionary processes needed to allow intelligent life to develop. It is a great pity that we seem unable to communicate to the world’s leaders and politicians how special Earth is, how delicate its equilibrium, how rich its diversity, and how easily this all might be lost, permanently and forever.
What else would you have studied if you had twice the time?
Mathematics, and in particular number theory. But only if I had had twice the ability!
What’s your favourite food?
I eat and enjoy almost anything, albeit veering towards vegetarian in recent years. A mixed salad with a suitable dressing or a selection of roasted vegetables is hard to beat. Come to think of it, I do have a particular soft spot for mushrooms!
Who’s your favourite musical artist or band?
The last concert I went to was Elton John in Rotterdam in 2009. It was billed as one of his final concerts but I think he’s still on tour today! The only group I’ve seen perform three times is the Tallis Scholars, going out of my way to listen to their performance of the sublime ‘Spem in Alium’ composed by Thomas Tallis in the 16th century. Does that count?
Do you have a pet peeve?
I am fighting a losing battle to have “kilometre” pronounced as kilo-metre rather than kill-om-eter, i.e. following the same stressed syllable as in nano-metre, milli-metre, and centi-metre. I also struggle with the common figurative use of the word “literally” – as in, “I literally died laughing” or “I was literally over the moon”. I find most TV adverts extremely annoying. How am I doing?
What ambition do you most want to realise before the end of your career?
After 30-years almost fully absorbed by these two space missions, Hipparcos and Gaia, I am getting huge satisfaction from looking into the scientific advances being made by others. It is excitement enough for me to be able to witness and wonder at these successes, the fruits of such immense efforts by so many people.
Professor Michael Perryman's own collection of weekly essays on Gaia, focusing on the science results, his interviews with some of the leaders of both the Hipparcos and Gaia projects, and some of his essays in recreational mathematics can be found at www.michaelperryman.co.uk.
Register for the Shaw Prize Lecture in Astronomy (online) on Friday 30 September 9:30AM UTC/5:30PM HKT, Professor Michael Perryman: ‘Why are we measuring star position from space?’
Professor Lennart Lindegren: ‘Fundamental concepts for global astrometry.’