Robert Ferguson Observatory

Sugarloaf Ridge State Park
Santa Rosa, CA 95404

Sugarloaf Ridge State Park is the home of Robert Ferguson Observatory, Northern California’s most active public observatory. It is also the largest observatory in the western United States completely dedicated to public viewing and education.
The dark night sky of Sugarloaf Ridge makes it a perfect location for stargazing and the observatory is open to the public on select weekends throughout the year for both night and solar viewing. Per-person fees are charged at the door for night viewing.
The Robert Ferguson Observatory is located near the group campground and is surrounded by a protective ring of hills, decreasing the light pollution from nearby cities. This astronomy observatory houses several telescopes. Our newest 40″ telescope has been installed. Come check it out.
The Observatory also provides Night Sky Classes, learn about the seasonal sky, with telescope observing after class.
The Robert Ferguson Observatory is open to the public only on scheduled monthly events. The observatory can be rented for private star parties and other events.


Robert Ferguson Observatory

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