Custer Observatory is an astronomical observatoryowned and operated by Custer Institute. Located in Southold, New York, facing Peconic Bay and Shelter Island, Custer's location boasts some of the darkest skies on Long Island. Long Island's oldest public observatory, Custer Institute was founded in 1927 by Charles Wesley Elmer , along with a group of fellow amateur-astronomers. The name was adopted to honor the hospitality of Mrs. Elmer, the Grand Niece of General George Armstrong Custer. In 1942, the Custer Institute was incorporated as a non-profit educational corporation in the State of New York. In 1938, the group purchased the land the institute presently occupies and initial construction was completed in the spring of 1939. The 100-seat lecture hall was added in 1945. In 1947, through donations by Charles Elmer and Mr. Polk, the 3-story tower/library and observatory dome were built. In 1954, Charles Elmer died; that same year, the Institute added the shed, which houses three sliding roof observatories. Over the years, Custer has acquired a large collection of telescopes of all sizes and descriptions. Most recently, 10" Zerochromat refracting telescope and is the largest of its type in the United States. This is in the main observatory dome." Our 10” refracting telescope was manufactured in England by Zerochromat Telescopes. Designed by award-winning optician Peter Wise, the telescope's unique dialyte lenses make it apochromatic, providing superior views of solar system and deep space objects. The folded light path construction uses mirrors to make the telescope a manageable size, allowing the long f/12 focal length telescope to fit in our dome. The telescope is attached to a computer-controlled Fornax 152 equatorial mount, permitting easy aiming and object tracking. The entire assembly can be raised/lowered on the Pier-Tech pier to accommodate most users’ heights, for comfortable viewing. Custer's Zerochromat telescope is the largest of its type in the United States." Previously, the dome was home to a 25-inch ObsessionNewtonian reflector. In order to bring the eyepiece of this telescope to a level that does not require observers to climb a high ladder, the optics on this telescope were modified solely by Custer's own Justine Haupt, an engineer at Brookhaven National Lab. Justine is currently involved in working on the camera for the LSST.
Custer Library
The Custer Library contains a wealth of Astronomy and Science books dating from the 19th century to the present. It also houses the Institute's videotape collection and 35mm astronomical slide collection. It contains National Geographic, Sky & Telescope, Astronomy, and Scientific American magazines dating back numerous decades. Membership to the Custer Institute grants access to their library.
Custer Museum
The Custer Institute Museum contains the following in its collection:
Henry Fitz, early Custer member and famous telescope mirror maker's Grinding Table.
A broken 1750s roadside Mile Marker, recovered by Custer members that was originally ordered by Ben Franklin when he was the head of the Colonial Mail system.
7x21 Ross Camera, f/7 with a 3" lens, accepting 8x10 and 4x5 inch plate film.
8" SCT f/11 Canon TV Lens
8" SCT f/5.6 mirror-lens
Public access
Generally the Custer Institute is open every Saturday evening, from dusk until midnight. Custer Observatory welcomes the general public to guided tours of the heavens—weather permitting. The Custer Institute also allows its lecture hall to be used for lectures, in-service courses for educators, concerts, theatrical performances, and other events.
