2023 Isaac Newton Medal and Prize
Professor James Binney for advancing the science of stellar dynamics and using strong physical intuition to widen and deepen our understanding of how galaxies are structured and formed.
Professor James Binney has had a deep and lasting impact on galactic and extragalactic astrophysics. His original contributions and leadership of the field have inspired generations of astrophysicists. His international standing is underlined by the award of the 2013 Eddington Medal of the Royal Astronomical Society, the 2015 Occhialini Medal & Prize of the Italian Physical Society, the 2013 Medaille de l'Institut d'Astrophysique de Paris, the 2010 Dirac Medal (Institute of Physics), the 2003 Dirk Brouwer Award of the American Astronomical Society and election in 2022 as an International Member of the US National Academy of Sciences.
Dynamically consistent galaxy models are vital tools for interpreting astronomical data, which are always incomplete and biased. Over decades, Binney has introduced new ways of building model galaxies, and of understanding the orbits of stars within them. This has led to insights that have significantly influenced our understanding of how galaxies, both elliptical and spiral, are structured, formed and evolve. He pointed out the importance of velocity anisotropy for elliptical galaxies, and the role that central black holes play in limiting star formation. With collaborators, he showed that spiral structure is important for the chemical evolution of galaxies, and made the case that galaxies like our own grow by bleeding gas from the vast reservoir of intergalactic gas. His contributions were key to establishing that ours is a barred galaxy and his work led to major revisions of the parameters that describe the bar and the Sun's orbit around it.
Binney’s work has often been characterized by original ideas ahead of their time which later become widely accepted within the community. These include the role of the active galactic nucleus in the evolution of cooling flows, radial mixing by spiral waves in galaxy discs and their impact on chemically identified populations, and helping to identify a serious flaw in early estimates of the optical depth to gravitational microlensing, a major discriminant between mass in stars and dark matter.
Binney’s books Galactic Dynamics, written with Scott Tremaine, and Galactic Astronomy, written with Michael Merrifield, are required reading for all students starting to work in galaxy physics and standard references for researchers in the area. In addition to his original research contributions, Binney is an inspiring college tutor, lecturer and supervisor, instilling in his students his ability to combine mathematical analysis, numerical simulation, physical insight and observational constraints to generate novel and exciting ideas.