Neta A Bahcall

Neta A. Bahcall is the Eugene Higgins Professor of Astrophysics at Princeton University and Director of the Undergraduate Program in Astrophysics. She is a leading researcher in observational cosmology with over 300 scientific publications. As an elected member of the US National Academy of Sciences and the American Academy of Arts and Sciences, she has made significant contributions to our understanding of the universe's large-scale structure and dark matter.

• Eugene Higgins Professor of Astrophysics (2007-Present)
• Director of Undergraduate Program (1993-Present)
• Editorial Board Member of PNAS
• Past Chair of the Astronomy Section of the National Academy of Sciences
• Past Director of the Council on Science and Technology of Princeton University

Bahcall's research focuses on observational cosmology, particularly dark matter, dark energy, and the large-scale structure of the universe. She pioneered the use of clusters of galaxies as cosmological tools, revealing a sub-critical universe with only ~25% of the mass needed to halt cosmic expansion. Her work on the cluster correlation function demonstrated unexpectedly large-scale structure in the universe up to ~150 Mpc, challenging standard cosmological models and leading to the 'biased galaxy formation' model of structure formation. She has shown that dark matter is primarily located in large halos around galaxies, with larger systems not being more dark-matter dominated compared to individual galaxies.

Bahcall's recent work has focused on cluster mass calibration using weak lensing techniques with the Hyper Suprime-Cam and ACTPol surveys, continuing her lifelong study of cosmic structure. Her publications demonstrate consistent focus on using observational data from large-scale surveys to constrain cosmological parameters and understand the universe's fundamental properties, with recent emphasis on SDSS-III data and advanced imaging from Subaru telescope.

• 2024 Henry Norris Russell Lectureship award (AAS)
• 2021 President's Distinguished Teaching Award (Princeton)
• Member, US National Academy of Sciences (elected 1997)
• Legacy Fellow of the American Astronomical Society (elected 2020)
• Fellow of the American Academy of Arts and Sciences (elected 2014)
• Antoinette de Vaucouleaurs Medal (2018-19)
• Cecilia Payne-Gaposhkin Prize (2012/13)

Bahcall has mentored numerous students and postdoctoral fellows throughout her career, contributing to over 300 scientific publications. She has served on numerous NASA, NSF, NAS, and Congressional Science committees, and was instrumental in developing science policies for the Hubble Space Telescope as the first Head of the Science Program Selection Office and Chief of the General Observer Branch at the Hubble Space Telescope Science Institute. Her work has helped establish standard methods currently used in cosmological investigations. Bahcall has been deeply involved in major astronomical surveys, particularly the Sloan Digital Sky Survey, where she chaired the Scientific Advisory Committee from 1990-1995.

Her research group has been at the forefront of using galaxy clusters as cosmological probes, developing methods to determine mass functions, mass-to-light ratios, and other properties that constrain cosmological models. She continues to lead research efforts connecting observational data with cosmological simulations to understand the universe's fundamental properties.