for their lifetime contributions to space astrometry, and in particular for their role in the conception and design of the European Space Agency’s Hipparcos and Gaia missions.
The Shaw Prize in Astronomy 2022 is awarded in equal shares to Lennart Lindegren, Professor Emeritus, Department of Astronomy and Theoretical Physics, Lund Observatory, Lund University, Sweden and Michael Perryman, Adjunct Professor, School of Physics, University College Dublin, Ireland for their lifetime contributions to space astrometry, and in particular for their role in the conception and design of the European Space Agency’s Hipparcos and Gaia missions.
Hipparcos, launched in 1989, measured the positions and motions of over 100,000 stars with accuracies two orders of magnitude better than ground-based observatories. Gaia, launched in 2013 and still operating, has measured the positions and motions of billions of stars, quasars and Solar System objects with far higher accuracy. The results from these missions offer an exquisitely detailed portrait of the distribution and properties of the stars in our Galaxy as well as unique insights into its formation and history, and impact almost every branch of astronomy and astrophysics. This award is also intended to honour the much larger community of astronomers and engineers who made Hipparcos and Gaia possible.
Astrometry, the first scientific discipline, is the measurement of the positions and motions of planets and stars. The early naked-eye star catalogues of Ptolemy (ca. 100–170 CE), Ulugh Beg (1394–1449), and Tycho Brahe (1546–1601) were supplanted in the last two centuries by telescopic catalogues of ever-increasing size and accuracy. However, by the late twentieth century, astrometry from ground-based optical telescopes encountered insurmountable barriers to further improvements, arising from atmospheric distortions, thermal and gravitational distortions of the telescopes, and the difficulties of stitching together data from telescopes in different continents.
The concepts of precision space astrometry date back to the 1960s, and these were first realized with the launch of the European Space Agency’s Hipparcos mission in 1989. Hipparcos measured the positions and motions of over 100,000 stars with accuracies 100 times better than ground-based observatories. By measuring small variations in stellar positions as the Earth traveled around its orbit (parallax), Hipparcos also determined distances to over 20,000 stars with uncertainties of less than 10%.
Lennart Lindegren was born in 1950 in Sweden and is currently Professor Emeritus of Lund Observatory, Department of Astronomy and Theoretical Physics at Lund University, Sweden. He received his PhD in 1980 from Lund University. He joined as a member of the teaching staff at Lund University and became Full Professor of Astronomy in 2000, serving until his retirement in 2017. During his time at Lund Observatory, he had served as the Director for six years. He was a member of the European Space Agency’s Hipparcos Science Team (1976–1997) and Gaia Science Advisory Group (1997–2000). He leads the scientific implementation of the Astrometric Global Iterative Solution in the Gaia Data Processing and Analysis Consortium and is also a member of the Gaia Science Team (2001–). He also served as Project Coordinator for the Marie Curie Research Training Network ELSA (2006–2010). He is a member of the Royal Swedish Academy of Sciences.
Michael Perryman was born in 1954 in Luton, UK and is currently Adjunct Professor, School of Physics at University College Dublin, Ireland. He received his Bachelor’s degree in Mathematics and Theoretical Physics in 1976 and obtained a PhD in 1980 from the University of Cambridge, UK. He joined the European Space Agency (ESA) in 1980 and was nominated as Project Scientist (1981–1997) for the Hipparcos mission, and subsequently Study Scientist (1995–2000) and Project Scientist (1995–2008) for the Gaia mission. During his service in ESA, he had been Professor of Astronomy (1993–2009) at Leiden University, The Netherlands. He held a joint position at the University of Heidelberg and the Max Planck Institute for Astronomy, Germany in 2010. A year later, he joined the University of Bristol, UK as visiting Professor of Physics (2011–2012). He has been Adjunct Professor at the University College Dublin since 2012.
