The UMD Department of Astronomy
cordially invites you to the

Mike A'Hearn Lecture

The Solar System Revisited with JWST: New Views, Discoveries, and Questions

with

Stefanie Milam
JWST Project Scientist for Policy and Science Community

Wednesday, April 2, 2025
3:30 -- 4:00 pm Pre-lecture Reception, Atlantic Building (ATL) 2400 Atrium
4:00 -- 5:00 pm Lecture, ATL 2400
5:15 -- 6:00 pm Post-Lecture Reception in Physical Sciences Complex (PSC) 1136

ABOUT THE TALK
The James Webb Space Telescope (JWST) has been astonishing the public and science community since the summer of 2022 after a nail-biting deployment sequence and extensive commissioning campaign. The complex space telescope operates with exquisite sensitivity at infrared wavelengths with imagers and spectrometers on board covering 1-28 microns. These instruments are already returning amazing spectra and images of small and large bodies in our solar system, revealing the composition and dynamic processes of these objects not readily accessible with other observatories or even planetary missions.
After only a few years, JWST has already provided fundamental insight into the composition and dynamics of planetary/satellite atmospheres/exospheres and rings as well as the composition of small bodies. We are learning more about the distribution of volatiles and processed materials across the different reservoirs of planetesimals and providing new observational constraints on the formation of the solar system. More importantly, the unprecedented resolution and spectral imaging are leading to new questions as well as revolutionizing planetary science for the outer solar system. The nominal launch and efficient operations in place ensure a JWST science mission lifetime of up to 20 years, enabling new discoveries and exploration for future generations. This presentation will highlight some of the amazing science in the solar system being revealed and some perspectives on what is to come.

ABOUT THE LECTURE
Ralph Pass (B.S. '68, M.A. '72, Ph.D. '78, mathematics) established the Mike A'Hearn Endowed Lectureship in 2020 in memory of UMD Distinguished University Professor of Astronomy Michael "Mike" Francis A'Hearn (1940-2017). Pass worked on all the manned Apollo missions and other NASA projects and credited A'Hearn as one of the top influencers of his academic life.

A renowned cometary astronomer, A'Hearn is perhaps most recognized as principal investigator and project leader of the spacecraft mission, Deep Impact, which resulted in the close exploration of two comets. However, his interests and reputation were broad and far beyond the cometary field. While UMD was his home, his reach encompassed the entire planetary astronomy community and the scientific community overall—both nationally and internationally. He was a brilliant scientist, a respected and influential collaborator, an inclusive team leader, and a most encouraging mentor to countless undergraduate and graduate students as well as young scientists. His legacy in the scientific community is remarkable.

Questions? Contact Barbara Hansborough at barbarah@umd.edu or 301-405-1508.