Nantucket Maria Mitchell Association and Nantucket Lights Releases Report on the Nantucket Sky Quality Monitoring Project

February 7, 2025

NANTUCKET, MA—– The Maria Mitchell Association (MMA) and Nantucket Lights are pleased to release the Nantucket Sky Quality Monitoring Project (SQM) report by Dark Sky Consulting, LLC. The joint program, launched in 2022, involves collecting night-sky brightness data from around Nantucket Island from citizen-scientists using handheld Unihedron Sky Quality Meters (SQMs) as measurement devices to study light pollution.

 

Observations were made from June 2022 to November 2024 at eight sites (Nantucket Town; Madaket Beach; Nantucket Elementary School; Nantucket Memorial Airport; Altar Rock; 'Sconset; Wauwinet; and Surfside Beach), a ninth site (Cisco Beach) was added in August 2024, for which only three months of data are available. These efforts establish a baseline for assessing the effectiveness of actions to mitigate light pollution going forward.

 

The distributions separate into two broad populations (high development: Nantucket Town; Nantucket Elementary School; and Nantucket Airport) and low/no development: (Madaket; Sconset; Wauwinet’; Surfside Beach; Cisco Beach; and Altar Rock). The darkest readings among the latter tend to occur in spring and summer. For high-development sites, the width of the distribution increases distinctly in summer and its mean shifts toward brighter values. We interpret this as due to an increased population on the island during the summer season.

 

 

 

The group follows the data collection procedure recommended by DarkSky International. Readings are taken under conditions intended to minimize interference from environmental influences. For example, reading does not commence until the end of astronomical twilight, which occurs about 90 minutes after sunset. Observers are encouraged to report only data taken under conditions of clear skies, which is sometimes not possible due to the vagaries of Nantucket weather. Additionally, they avoid obtaining data when the Moon is above the horizon to limit the contaminating effect of its light. Readings are taken after the conclusion of astronomical twilight during the week between the last-quarter and new Moon phases.

 

Analysis of the night-sky brightness measurements since 2022 show that the data are broadly valid and reproducible, and that outlier values can largely be explained by the influence of environmental conditions. Distributions of measurements across various cuts (location, year) are normal as expected for random sampling of the assumed underlying “populations” of night-sky brightness values. And there is not a great deal of night-sky brightness variation from one year to the next, either on a per-site basis or island-wide. From this, we can broadly conclude that light emissions on Nantucket have, in recent years, increased only at a very slow rate. The Nantucket Dark Sky Monitoring Project continues to be monitored, and data is being collected and analyzed.

 

You can find more detailed information on the Nantucket Island Night Sky Quality Report here:
 
Nantucket-Report-FINAL-250123.pdf


Nantucket-Annex-FINAL-250123.pdf


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 female 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


###

For Immediate Release

February 7, 2025

Contact: Joanna Roche

jroche@mariamitchell.org

Recent Posts

By Jascin N. Leonardo Finger August 25, 2025
With Margaret Harwood’s growing collection of glass plates of the night skies needing better storage and Harwood in need of a warm place to work in the fall and spring, the Hinchman family gave $5,000.00 towards the construction of a study and storage area at the MMO. The MMA was able to raise the remaining $1,500.00 needed and the Astronomical Study was built in 1922 between the Observatory and Mitchell House. The Astronomical Study was built as a memorial to Eliza R. Mitchell, the Treasurer of the MMA from 1905 to 1918, and a family member. JNLF
By Jascin N. Leonardo Finger August 18, 2025
August 17{1857} Today we have been to the far-famed British museum. I carried as “open sesame” a paper given to me by Prof. Henry asking for me special attention from all societies with which the Smithsonian {is} connected . . . . The art of printing has brought us incalculable blessings, but as I looked at a neat manuscript book by Queen Elizabeth copied from another, as a present to her Father I could not help thinking that it was better than worsted work! On August 2, 1857, Maria Mitchell and the young woman she was accompanying as a chaperone, Prudence Smith, arrived in Liverpool England for their European tour. Maria Mitchell’s “open sesame” was a letter of introduction – she went with several. She would find that the doors were thrown open for America’s first woman astronomer – she was that well known in America and abroad. She would become quite close to Sir George Airy, the British Astronomer Royal, and his wife Richarda, as well as the astronomical Herschel family. JNLF
By Jascin N. Leonardo Finger August 11, 2025
After many years on the making, we are happy to officially announce the re-opening of the Maria Mitchell Vestal Street Observatory – also fondly referred to as the MMO. As you may have seen on the Maria Mitchell’s Attic bog, this has truly been more than a multi-year labor of love. Way back in 2016, we began the first steps with a structural assessment by structural engineer, John Wathne of Structures-North. That, coupled with an earlier Conservation Assessment Program grant from Heritage Preservation and supported by the Institute for Museum and Library Services that allowed the MMA to hire architectural conservator, Michael Devonshire, began us on our path to conserve the historic MMO. Grants from the Community Preservation Act and the M. S. Worthington Foundation supported the conservation work on the 1908 Observatory and its 1922 Astronomical Study. Masonry and grout were repaired, rusted iron lintels over windows and doors were replaced with steel and work was completed to the “parapets.” This sounds simple – it was not – it was a multi- year project to work with the masonry and to create a matching grout. Wayne Morris, the mason, became a fixture on Vestal Street again – as he did all the masonry conservation and work on the exterior of the Research Center. Once the MMO’s exterior was weather tight and the interior masonry work completed, the rest of the crew moved in to conserve the plaster, re-paint, and conserve the original 1922 bookcases and woodwork in the Study. Paint was removed from the dome bringing it back to its original glory. Cement floors were cleaned and treated and electrical wiring was updated and new lighting put in the Study. A major renovation was also conducted concerning the “Seminar Room” – a 1987 addition to the west of the MMO – which was completed in 2024. This was funded in large part by Mitchell family descendant and former (now honorary) MMA Board Member, Richard Wolfe. New office spaces were created for astronomy staff, updates were made to the astronomy intern workspace and meeting space, and a new accessible bathroom was completed. We also owe a huge debt of gratitude to two other board members in this work, particularly with the Seminar Room – Elizabeth Markel and John Wise. We would like to thank everyone for their roles in making this long journey a success and for doing all of this important work. Thank you does not express it well enough – they have truly all been heroes of the MMO. We are beyond grateful. THANK YOU and WOW it all looks incredible! Wayne Morris, Mason John Wathne, Structures-North Consulting Engineers Wise Construction – John Wise, Pat Marks, “Chip” and Crew Elizabeth Markel, Elizabeth Markel Interiors Ellis and Schneider Electrical Benjamin Normand, Normand Residential Design W. B. Marden Plumbing, Robert and henry Butler, Mike Gillies, and Derek Kevin Wiggin and Crew, KW HVAC INC Pen Austin, plasterer Evita Caune, Riptide Finishes Brian Connor and Crew, Brian Connor Electric Inc. Adam Zanelli and Crew, Nantucket Heritage Painting Michael Devonshire James Lydon and Sons and Daughter Michael Stefanski, Seed to Stone Landscaping Matthew Anderson and Maxx Ray Michael Gault Pioneer Cleaning Brook Meerbergen, M.A. Supply / Green Mountain Window Co. Nantucket Networks Polygon Group JNLF
Show More