Astronomy at Williams College spans the very old and the very new. The Hopkins Observatory is the oldest existing astronomical observatory in the United States and houses the earliest telescope by the famous maker Alvan Clark, whose company ultimately made the still-largest refracting telescope. At the same time, current astronomy faculty and students carry out research with some of the world’s most advanced telescopes.

We offer courses for both majors and non-majors. Many astronomy courses take advantage of on-campus observing facilities that include a 24-inch computer-controlled telescope with CCD detectors for imaging and spectroscopy, along with our computer network for image processing. Specialized telescopes for observing the Sun are adjacent.

Students interested in majoring may choose either to be an Astrophysics major or an Astronomy major, both administered by the joint Department of Physics and Astronomy.  Learning objectives and student achievement goals for both majors are stated here.

Our students participate broadly in faculty research. In addition, Williams College is a member of the Keck Northeast Astronomy Consortium, comprised of astronomy faculty and students from eight liberal arts colleges in New England and the Mid-Atlantic states. Among KNAC’s activities are a summer exchange program for astronomy research students and a fall student research symposium.  Williams College also participates in the educational aspects of the Zwicky Telescope Facility of Caltech’s Palomar Observatory, which links the 200″, 60″ and 48″ telescopes on Palomar Mountain for time-domain astronomy.  After you have finished browsing our pages, you might want to explore some of these other astronomy sites.

For more information about astronomy at Williams, please feel free to contact us directly at the address below or

Look for us on Instagram! (@williamsastronomy)