Treworgy Planetarium

Stars: The Original Global Positioning System

To you, they’re pretty. To sailors, they were the difference between life and death. And in the Treworgy Planetarium at Mystic Seaport, you can get a lesson in celestial navigation using the stars, planets, and heavenly bodies of the season. The Treworgy Planetarium itself was designed specially for Mystic Seaport by Armand Spitz in 1960.

Each season the Planetarium’s daily program shows you how to locate and identify the stars, planets, and constellations in the sky at that time of year. These live programs last about 30 minutes and include a few basic points about using the stars for navigation. Slide projectors in the Planetarium are used to show images of special interest. Different programs and presentations are offered throughout the year, from “Finding Your Way By the Stars” to “Celebration of Winter Stars and Light.”

Inside the Planetarium

Treworgy Planetarium

Treworgy Planetarium

The stars and planets are projected overhead onto the surface of a 30-foot diameter dome. About 1,200 can be shown. The planets, sun, and moon are projected by individual lights.

Other special effects that can be projected are a geocentric view of the earth, circles, triangles, meridians and coordinate grids for navigational purposes.

Download the Sky Guide

A special guide designed for our youngest astronomers! Download our Sky Guide and step into your own backyard to follow Megrez in the Big Dipper to Arcturus and Antares; find the ice cream cone in Boötes; follow Vega through the belly of Hercules to Arcturus, and more.

Download our Sky Guide