Welcome to the Custer Institute & Observatory

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

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, museum, and gift shop. Frequent lectures, classes,concerts, art exhibits and other special events.


Custer Links

Members' Night: Members Only!

Observing, making, fixing, playing, and more!

Ordinarily the last Friday of each month are Members' Nights.

Custer is closed to the public on Members' Nights.
As a member, this is YOUR time to enjoy Custer and meet with other members.


A Members-Only (and their guests) evening for mingling, observing, enjoying the observatory and its resources, discussing Custer's present and planning its future together.

Activities range from repairing telescopes or other equipment, grinding mirrors, cleaning, astrophotography, watching Star Trek, playing games, and of course, observing.

We often have dinner together. Sometimes a restaurant, take out, or we cook or BBQ at Custer. We like food!