Welcome to the Custer Institute & Observatory

Long Island's oldest public observatory (est. 1927)

Support Custer through General Donations, Building & Restoration Project, and by becoming a Member!

All observing is done out in the open air, under the stars. Dress appropriately.

For the Curious

The Custer Institute and Observatory is Long Island's oldest public observatory (est.1927). Open to the public every Saturday evening from dusk until midnight, our staff of volunteers will give you a tour of the facilities and the night sky through our powerful telescopes. Custer has a library, exhibit room, and gift shop. Frequent lectures, classes,concerts, art exhibits and other special events.

Updated: 05/8/24

Saturday Night Observing: Open 8pm-Midnight

Check our weather and the moon phase

Weather permitting, Saturday Night Observing is from 7pm to midnight where volunteer Staff provide guided tours of the sky.

Check back often for the lastest information regarding programs and news.

Everyone loves the moon! Check the phase of the Moon here and remember, less moon = darker skies which is what you need to see many deep sky objects such as those found in the Messier Catalog or the NGC Objects. But whether the Moon is just a sliver or full, it's always great to see through our telescopes!

As a volunteer organization, we can really only guarantee to answer the phone Saturday nights when we are there. Check back here and our facebook page for the latest information.




This performance features the Rites of Spring Ensemble, a new group that embodies the spirit of the new music culture and is dedicated to performing innovative, collaborative, and exciting works of living composers and the contemporary works from composers of the recent past. Whether you're a classical lover or a lover of extraordinary experiences, Music in The Sky pushes the boundaries of a traditional music event. This program presents a very exciting evening of music and stargazing! New Music Under The Big Sky aims to bring people together and focusing on what is happening today in the global arts world. Come and slow down with us, be immersed with music, lights and stars!

$40 Adult, $30 Custer Observatory Members and Friends of R o S, Children Under 16 FREE. Attendance to this in-person performance will be limited - reserve your seats early! Due to the outdoor nature of this program, a rain date will be scheduled as needed.

Please bring a blanket or chair to enjoy this outdoor presentation.

  • Jongo by P. Bellinati
  • Melodia Sentimental by Heitor Villa-Lobos
  • Gabriele Leite, guitar

  • Serenade by Lou Harrison
  • I. Round
  • II. Air
  • III. Infiniite Cannon
  • IV. Usul - "Little Homage to Sinan"
  • V. Sonata
  • Gabriele Leite, guitar
  • Eduardo Leandro, Percussion

  • Dressur by Mauricio Kagel
  • Renan Proenca, Percussion I, Eduardo Leandro, Percussion II, Khesner Oliveira, Percussion III

R o S Ensemble is a collectively organized group of musicians dedicated to performing classical music and creating new artistic works at the highest level. Based on the East End of Long Island, the ensemble is committed to the idea that new music belongs in every community and implements this mission through touring and outreach to connect with audiences and artists, focusing specifically on bringing music to locations out of the reach of many music organizations. Created by founder Paolo Bartolani, pianist and artistic director of Rites of Spring Music Festival, R o S Ensemble is dedicated to connecting communities across the East End of Long Island and the United States through the development and performance of music across the country. This ensemble explores, performs and studies new concepts of notation, extended performing techniques, group improvisation and group composition, including other aspects of performance centered around the latest developments in sonic art. Their experience is extensive: from creating and performing music in unconventional venues, to site-specific projects that combine music, natural environment, and history, to collaborating with like-minded artists, performers, and thinkers, and offering a platform for all whose work demands it.

Registration/ticket portal is here:




Spring is the season of renewal, rejuvenation, growth and galaxies...lots and lots of galaxies! What better way to celebrate May the Fourth than at Custer Observatory's first night sky tour of 2024! Join stargazing lecturer Randall DiGiuseppe of the Custer Institute & Observatory as he guides you through a multitude of galaxies far, far away including the Leo Triplet, galactic marvels of the Virgo Cluster and the Sombrero Galaxy.

This event is being held outdoors and is open to everyone. Just bring an inquisitive mind, a blanket or chair 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.

Following the presentation, Observatory staff will provide guided tours of the night sky (weather permitting) through the many telescopes on site, including the apochromatic Zerochromat telescope in our historic observation dome.

$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 bring a blanket or chair to enjoy the presentation.

Registration/ticket portal is here:
June 22

4:30 pm


Join members of Custer Institute & Observatory for our annual membership meeting and Board elections. This meeting will be held in-person and will be followed by an outdoor BBQ and stargazing. This is a free, members-only event.

Regular members of the Institute in good standing are eligible to vote in the elections of the Board. We hope to see you there!

July 20

4:30 pm

Custer Board Meeting.

Members welcome.

This Week @NASA

May 2024 Skywatching Tips from NASA

NASA TV airs a variety of regularly scheduled, pre-recorded educational and public relations programming 24 hours a day on its various channels. The network also provides an array of live programming, such as 24-hour coverage of International Space Station events (spacewalks, media interviews, educational broadcasts), and rocket launches.