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It's Here!
Our new 40"-diameter Telescope!
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Coming Events

(Observatory is open to the public
ONLY for scheduled events).

Star Party

Saturday, February 6

Solar: 11am-3pm
Star Party begins 7pm


Night Sky Classes

Jan. 12, Feb. 9, Mar. 8
Mar. 29, Apr. 5, May 3

Learn about the seasonal sky, with telescope
observing after class. Details


40" Telescope!
A new 40"-diameter telescope replaces our
previous 24" telescope. In astronomy, bigger is better, and our team designed the biggest telescope that would fit. And...no more ladder climbing! The 40" is the largest publicly-accessible optical telescope in California. Our "Project 40" blog details the design, mirror grinding and construction, done entirely by RFO volunteers! See our Telescopes page for technical details.

Here's a photo of it in place prior to enclosing the frame. See that mirror? It's a big, big light bucket!

A new home is being sought for the 24" scope. $10,000 or best offer. Contact mhillestad at rfo.org for details.


"Before Telescopes"
From Stonehenge to Galileo

A new series of
public presentations on the History of Astronomy, each lecture focusing on a different point in history.

Exploring what early astronomers learned without telescopes—just sharp eyes and sharp minds— is a good way to understand the basics of observational astronomy.

Presentations are given free during public
Star Parties

RFO at nightAbove: The Observatory at night. Photo by Mark Hillestad
Top right photo of Refractor Telescope by Jerry Telfer

Rent an

Yes, you can!
Treat your family, friends,
or group of up to 50 people
to a night with the stars!


Weather Forecast

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Sugarloaf Ridge
State Park

"Team Sugarloaf" operates Sugarloaf Ridge,
including the campground.
Team Sugarloaf is a unique partnership of five nonprofit organizations that have worked tirelessly to keep our park open.  

Partners are: Sonoma Ecology Center; United Camps, Conferences and Retreats; Valley of the Moon Natural History Association; Sonoma County Trails Council; and Valley of the Moon
Observatory Association.  

With expertise in campground operations, ecological restoration, astronomy, trails management, and volunteer recruiting and training, Team Sugarloaf is creating new opportunities for Sugarloaf Ridge and its visitors.  Visit sugarloafpark.org for more information.

Come to stargaze and camp at Sugarloaf Ridge!