Custer Institute and Observatory is Long Island's oldest public observatory - open from 7 pm to midnight on Saturdays! 

Explore the night sky with our volunteers, powerful telescopes, tours, and live events.

Silhouette of a person under a colorful night sky filled with stars and the Milky Way.

Custer Institute is recognized as an official Minor Planet Center Observatory

MPC Observatory Code W51

Join us every Saturday night for public observing sessions, where you can explore the cosmos through our powerful telescopes.

When the skies are clear, our knowledgeable volunteer staff will guide you on a tour of the stars, planets, and beyond.

Saturday Night Public Observing
Doors open at 7 PM
Observing from dark until midnight (weather permitting)

All observing takes place outdoors—please dress appropriately. Seasonal hours and times of darkness may affect skywatching times.

EVENTS

Outdoor Events: Most events take place on our lawn. We encourage you to bring a blanket or chair to make your experience more comfortable.

Rain Dates: Rain dates (when necessary) will be noted on our website, social media, and/or Eventbrite for your convenience.

Stargazing Nights @ Silver Sands

Friday, November 6. 6:00pm - 8:00pm

Custer Observatory returns to Silver Sands Motel & Beach Bungalows on Friday, November 6th from 6:00–8:00pm for an evening of stargazing on the boardwalk at 1400 Silvermere Road in Greenport.

Guided by the team from Custer Observatory, guests will explore stars, planets, and distant galaxies through high-powered telescopes set up along the beach overlooking Pipes Cove. This time, we’re looking for the Pleiades (M45), better known as the Seven Sisters. A small gathering of brilliant blue-white stars you can spot with the naked eye, some 440 light-years from Earth. Look a little closer and there’s much more to the story: the cluster is actually home to over 1,000 stars.

We’ll also turn the telescopes toward the Double Cluster in Perseus, two spectacular groups of stars some 7,500 light-years away, before getting a closer look at Saturn’s rings and, conditions permitting, its largest moon, Titan.

To keep the night comfortable, complimentary hot cider, hot cocoa, cosmic brownie bites, and warm blankets will be available as you take in the sky above. Admission is $15 for adults and $5 for children, with all proceeds directly supporting Custer Observatory and its mission to bring astronomy to the community.

Turn the experience into a full evening by pairing stargazing with dinner at The Boathouse before or after the program. Whether you're deeply familiar with the night sky or simply curious, this is an intimate and memorable way to spend an evening on the North Fork.

Space is limited so reserve now! In the event of overcast skies or rain, the event will be postponed and held on Friday, November 20 at 6:00pm.

Please note that this is a weather-permitting event. Event changes will be emailed to the address provided at checkout and posted at www.custerobservatory.org and on this Eventbrite page. Please check for weather updates before arriving.


Winter Wonders of the Night Sky

Saturday, December 5. 6:00pm & 8:00pm

Learn how to explore and navigate the winter night sky, including the constellations visible this season and stories behind them!

Randall DiGiuseppe, Custer lifetime member and presenter, will be your guide to the awe-inspiring objects that grace our winter night sky such as the Pleiades, Orion's stars and nebulae, and other winter constellations. The event will begin with a talk indoors followed by guided observing outdoors to view some of the objects covered during the presentation. Observatory staff will also provide tours of the night sky (weather permitting) through the many telescopes on site, including the apochromatic Zerochromat telescope in our historic observation dome. Bundle up, look up and take in what our winter night sky has to offer. Then warm up inside with a cup of hot tea or cocoa!

This event is open to everyone. Just bring an inquisitive mind and your imagination.

Randall DiGiuseppe is a professional artist, lecturer, telescope builder and amateur astronomer for over four decades. He is a lifetime member of the Custer Institute and Observatory and recipient of the Astronomical League’s Messier Award. He conducts lectures on the dynamics, history and art of the night sky throughout the country.

$5 Adult, $3 Children Under 16, Observatory Members FREE. Your donations make it possible to offer programs like these and are greatly appreciated. Due to limited space, registration is strongly encouraged.

Please note that this is a weather-permitting event. In the event of overcast skies or rain, the event will be postponed and held on Saturday, December 12. Event changes will be emailed to the address provided at checkout and posted at www.custerobservatory.org and on this Eventbrite page. Please check for weather updates before arriving.

PROGRAMS + RESOURCES

  • Astronaut on the moon holding a yellow umbrella with Earth in the background.

    WEATHER

    Clear Skies Ahead!

    Find the latest weather forecasts tailored for astronomers, including cloud cover, precipitation, dewpoint, wind conditions, and Moon phases. Our easy-to-read key helps you decide if it’s a perfect night to bring out your telescope!

  • Silhouettes of musicians and text "Music Under the Stars The Music Project at Custer Institute & Observatory."

    THE MUSIC PROJECT

    Bringing music and stargazing together at Long Island’s oldest public observatory, tMP blends the performing arts with science and discovery. A unique stargazing experience follows each performance where audiences are invited to explore the night sky with guidance from our expert volunteer staff, using our historic observation dome and an array of on-site telescopes.

  • WHAT'S UP?

    Skywatching highlights each month, provided by NASA.

  • Telescope on tripod with accessories in a grassy field with trees in the background.

    RESOURCES

    Whether you're a seasoned astronomer or just starting your journey into the cosmos, our collection of resources will help guide you.

  • Blue background with white and gold text reading "Custer Institute & Observatory Scholarship Program" and a stylized star and comet graphic in the top left corner.

    SCHOLARSHIP

    Supporting the Next Generation of Scientists & Innovators. Available to High School Seniors throughout the North Fork.

  • Illustration of Custer Institute Observatory with text "Honey of the Stars, 100% Pure Local Honey, Custer Institute Observatory, Southold, New York" and "Custer HoneyBee Club" on a building, under a starry sky.

    HONEY BEE CLUB

    Custer's Honey Bee Club is an educational program focused on environmental sustainability and honeybee stewardship.

    Send an email to learn more.

Support the North Fork Dark Sky Coalition

Take action to protect our night skies:

  • Pledge to turn off unnecessary lights and spread awareness,

  • Update Your Lighting by using dark sky-friendly fixtures and warm-toned bulbs, and

  • Become a Partner to advocate, educate, and support local Dark Sky initiatives.

Take the pledge and join the North Fork Dark Sky Coalition

Night sky with Milky Way over waterfront building and boats at a dock.

AFFILIATIONS + SUPPORTERS + PARTNERS

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