This Aspen Winter Conference will bring together theorists and observers to exchange recent results and prepare for the era of JWST. We are planning for an in-person meeting. Please see the Aspen Center for Physics' COVID-19 policy statement for information about protocols related to COVID-19, including testing, masking, and cancellation.

Globular clusters in the local Universe are common, bright tracers of galactic halos. Their progenitors were plausibly the first gravitationally bound baryonic systems to form in the Universe and may represent the dominant mode of star formation at early times. The ancestors of globular cluster are widely expected to be visible in deep James Webb Space Telescope (JWST) images, providing insight into the earliest stages of star formation at high redshift (a key science goal of JWST). Since they are thought to form in high-pressure environments during epochs of intense star formation and are dense enough to resist tidal disruption over the age of the Universe, globular clusters link the small-scale physics of star formation with the large-scale physics of galaxy formation, and the properties of the early Universe with the present day. There is much work to be done to understand exactly how they formed and the connection of that process to the collapse of early dark matter haloes. Vigorous effort is underway to explore the formation of globular clusters within cosmological simulations, with attendant predictions for JWST, in addition to other observatories. In parallel, dynamical modeling of both systems of globular clusters and internal motions for individual clusters has been galvanized by transformational Gaia astrometric data. The long-standing question of the dark-matter content of globular clusters is under new investigation. Further, ongoing imaging and spectroscopic surveys are improving quantification of the fossil record held in the properties of globular clusters in the local Universe.

Science Organizing Committee:
Mike Boylan-Kolchin (The University of Texas at Austin)
Jean Brodie (Swinburne University)
Ray Carlberg (University of Toronto)
Søren Larsen (Radboud University)
Rosie Wyse (Johns Hopkins University; SOC chair)
Massimo Stiavelli (Space Telescope Science Institute; consultant)