Hopkins Observatory holds national legacy of discovery

In 2012, the College’s astronomy department used the seven-inch refracting telescope in Hopkins Observatory to look at a star in the night sky for the first time in years. Though not the first astronomical observatory in America,  Hopkins Observatory, dedicated in 1838, is the oldest surviving observatory in the United States, and the telescope within its main dome is over 150 years old. Two years ago, a colleague of Director of Hopkins Observatory and Professor of Astronomy Jay Pasachoff, who is an expert on telescopes created by Alvin Clark in the 1800s, traveled from Cambridge to fix the focusing mechanisms of the old telescope, rendering it usable once again.

Hopkins Observatory takes its name from Albert Hopkins, brother of Mark Hopkins, President of the College and a professor at the College from 1829 to 1872, who was the driving force behind the development of astronomy as a major at the College and behind the observatory itself. A minister whose interest in religion was tied to his interest in astronomy, Hopkins would later praise the observatory as a means through which students could focus their attention on “the fathomless fountain and author of being, who has constituted matter and all its accidents as lively emblems of the immaterial kingdom.”

In a 1991 article for the Journal of Astronomical History and Heritage, Pasachoff reported on his own communication with historian Marc Rothenberg, who called Hopkins “a representative of an entire generation of teachers of astronomy,” whose distinguishing factor was “his ability to leave behind a permanent physical legacy – the observatory.”

The process of building the observatory began in 1834, when Hopkins traveled to Liverpool with a grant from alumni and purchased several pieces of astronomical equipment that can still be found in the Mehlin Museum of Astronomy, located within the old Observatory building, today. In 1836, construction began on a permanent observatory.

To fund the $2075 cost of the observatory upon his return, Hopkins received $1200 from trustees and $400 from a friend; he paid the last $475 out of his own pocket. The domed room that held the telescope, which is located in the center of the old Observatory building and decorated with gold stars mirroring constellations, served as “perhaps the earliest American example of what we today call a planetarium,” according to Pasachoff.

A local newspaper clipping from 1841 states that in 1838, at the dedication of Hopkins Observatory, Hopkins proposed that the foundation of the observatory was the idea “that nature is to be studied rather than books,” and that “in their worship of the practical, men were losing sight of the moral.”

The original telescope in the observatory was replaced in 1852 by a seven-inch refracting telescope. The seventelescope, restored in 2012, was the first professional telescope created by Alvan Clark. Clark used the College’s commission to start his own company, Alvan Clark & Sons, and later went on to build the largest refracting telescope ever created.

Originally, the observatory sat in the center of Greylock Quad, though it was shifted to the south end of the quad and rotated slightly in 1908. In 1961, the building was moved once more to its current location in Currier Quad. 1988 marked the sesquicentennial of the Hopkins Observatory, in honor of which the Clark Art Institute put on an exhibition of astronomical art. In 1991, the College installed a 24-inch, professional grade reflecting telescope on top of Thompson Physical Labs, and upgraded it substantially four years later thanks to funding from the National Science Foundation.

Today, the old observatory is used as a center for astronomy outreach and education of the outside world. Student Teaching Assistants give planetarium shows on Friday nights, some private and some for the public. They take place in the Milham Planetarium, named after Willis Milham, the third director of the observatory, who taught at the College for 47 years, longer than any professor other than Mark Hopkins. The building also contains the Mehlin Museum of Astronomy, in honor of Theodore Mehlin, the fourth director, which houses all but one of the original astronomical instruments Hopkins brought back to the College in 1834.

For the astronomy department, the presence of this historical observatory is a central part of the astronomy-related activity on campus. Overseeing an observatory with the first Alvan Clark telescope is “historically significant and fun,” according to Pasachoff, in that it overlaps with his interests in both history and astronomy. Students who step into the building today are sharing the experience with generations of students and visitors, including Ralph Waldo Emerson himself, who visited in 1865. “What is so good in a college as an observatory?” he wrote afterwards in his journal. “The sublime attaches to the door and to the first stair as you ascend; that this is the road to the stars. Every fixture and instrument in the building, every nail and pain has a direct reference to the Milky-Way, the fixed stars, and the nebulae. And we leave Massachusetts and the Americas and history at the door, when we came in.”

  • J M

    Eph who has taught the longest at Williams–

    “Willis Milham, the third director of the observatory, who taught at the College for 47 years, longer than any professor other than Mark Hopkins.”


    “Professor of Art EJ Johnson ’59 taught at a large state university in between studying at Williams and teaching at Williams. Entering his 49th year at the College, Johnson said ..”
    from another article in this issue about Williams alumni returning to teach

    OR, someone else?