For innovative advances in our understanding of the hierarchical formation of the Milky Way and constraints on the galactic potential.

For pioneering research into complex astrophysical chemistry, including foundational work on chiral and aromatic molecules in the interstellar medium. 

For his insightful research using supernovae as cosmological probes.

For the the upper-level undergraduate or graduate textbook, Understanding Stellar Evolution (IOP Publishing Ltd., 2017).

For his seminal contributions to theoretical astrophysics, from the formation of stars and planetary systems to the structure of disk galaxies; for his sustained leadership in the global astronomical community; and for his elegant textbooks that have influenced generations of astronomers.

For the the upper-level undergraduate or graduate textbook, Understanding Stellar Evolution (IOP Publishing Ltd., 2017).

For her pioneering work expanding and pushing boundaries in the field of small-body solar-system observational science, and for her transformative contributions that have shaped the broader field of planetary science. 

For the nation-wide impact of her work educating teachers as Director of the Exploratorium Teacher Institute, and for the development of novel educational programs aimed at non-astronomers as Chief Executive Officer of the Astronomical Society of the Pacific. 

For her leadership in observational studies of gas-giant exoplanet formation, evolution, and impact on planetary systems.

For novel explorations of the relativistic universe that have revealed fundamental properties of neutron stars. 

For her pioneering contributions pushing the boundaries of ultraviolet/visible photon-counting charge-coupled devices, her sustained infusion of related technologies across multiple fields, her diligent engineering leadership, and her consistent and attentive mentoring of early-career instrumentation researchers.

Stephen Taylor and the NANOGrav Collaboration

For the transformative discovery of compelling evidence for a nanohertz gravitational-wave background, identified via more than 15 years of pulsar timing observations.

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For her leadership of foundational work that is greatly advancing our understanding of explosive astrophysical transients and their host galaxies.