Glass Plate Photographic Collection

Jascin N. Leonardo Finger • August 4, 2025

With the help of Edward Pickering from Harvard, the MMA was able to develop a research program and realized that a photographic telescope would be necessary. Funds were raised and by November 1913, a 7.5-inch photographic telescope was installed. Using Maria Mitchell’s 5-inch Alvan Clark telescope as a guide for the larger photographic telescope, the photographic telescope had a lens from Thomas Cooke and Sons of York, England and a cast-iron pier, mount, and clockwork by Alvan Clark & Sons in Cambridge, MA. The pier, mount, and clockwork are still present in the MMO – the pier and mount still utilized but by a 17-inch research telescope purchased with a grant from the National Science Foundation.


The glass plates taken of the night sky at the MMO total more than 8,000 and they are still utilized for research. They capture a moment in the night sky that can never be captured again – just like a regular photograph. In order to capture the image of the night sky, exposures could last for as long as three hours or more. Glass plates were heavily used for researching variable stars. They also afforded opportunities for new discoveries that could go unnoticed when one looked through a telescope by eye. Glass plates are gelatin-coated dry plate negatives that first came into use in the 1870s. They were utilized well into the late twentieth century particularly because they did not shrink or deform like plastic film. At the MMA, we continued to take glass plates of the night sky until 1995 when we had the opportunity and funding to update to a CCD camera – charge-coupled devices. While the CCDs provided many improvements, they still did not have the detecting area and resolution of glass plates. Technology continues to evolve, and the MMA with it, as we work with new methods to capture the night sky photographically.


JNLF

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By Jascin N. Leonardo Finger October 6, 2025
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October 2, 2025
NANTUCKET, MA— —The Nantucket Maria Mitchell Association (MMA) announces that it will host its new Director of Astronomy, Jackie Mlingo, PhD., as a featured presenter for its October Science Speaker Series. The presentation will take place on Wednesday, October 15 at 7pm in person at the MMA Research Center, 2 Vestal Street, and via Zoom. The event is FREE to all. Have you ever noticed the dark spots that sometimes appear on the Sun’s surface? These “sunspots” are just one example of star spots—mysterious patches that appear on stars across the galaxy. Far from being simple blemishes, star spots reveal the powerful magnetic forces at work inside stars, forces that also drive solar storms and shape the space weather that can impact entire planetary systems. In this talk, Dr. Milingo will share her research on star spots and how she uses them as a window into teaching undergraduates the process of scientific discovery. She will also explore how science can reach far beyond the classroom—bringing STEM into everyday spaces and sparking curiosity across communities, from kindergartners to lifelong learners. Dr. Jackie Milingo is an observational astronomer who earned B.S. degrees in Physics and Astronomy from the University of Kansas, and a Ph.D. in Astrophysics from the University of Oklahoma. Her research is currently focused on understanding magnetic activity cycles in sun-like stars through long-term studies of starpots. Dr. Milingo joins the MMA after a year-long AAAS Science and Technology Policy Fellowship at the U.S. National Science Foundation, where she was a Fellow in the Office of Legislative and Public Affairs, as well as the Astronomy Division in the Math and Physical Sciences Directorate. Before her fellowship, she was a professor in the Physics Department at Gettysburg College for over twenty years where her work included mentoring undergraduate research students. Dr. Milingo joined the staff of the MMA in early September after a year-long, worldwide search for a new astronomer. She becomes the eighth MMA Astronomer and Director of the Astronomy Department of the MMA since Margaret Harwood, the MMA’s first astronomer, served from 1916 to 1957. Dr. Milingo has spent her career committed to generating transformative experiential learning opportunities, contributing to public education and outreach, removing barriers for students, and changing the conversation and learning spaces in astronomy, physics, and STEM in general. This event will be held both in person and via Zoom. Pre-registration is required to attend either option. To register for the free, in-person event, use the registration link below: https://112458a.blackbaudhosting.com/112458a/October-Science-Speaker-Series--Dr-Jackie-Milingo To register for the free, Zoom option, use the registration link below: https://us06web.zoom.us/webinar/register/WN_5q4kXF2rRHi8iWbFPkLN5w The Science Speaker Series is generously sponsored by the Maria Mitchell Association’s lead sponsor, Bank of America The Maria Mitchell Association was founded in 1902 to preserve the legacy of Nantucket native astronomer, naturalist, librarian, and educator, Maria Mitchell. After she discovered a comet in 1847, Mitchell’s international fame led to many achievements and awards, including an appointment as the first professor of astronomy at Vassar College. Maria Mitchell believed in “learning by doing” and today that philosophy is reflected in the MMA’s mission statement, programs, research projects, and other activities. The Maria Mitchell Association operates two observatories, a natural science museum, an aquarium, a research center, and preserves the historic birthplace of Maria Mitchell. A wide variety of science and history-related programming is offered throughout the year for people of all ages. ###
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“If you don’t look, you don’t see. You have to go and look.” -Edith Andrews
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