Winter - 2026 - Public Observing
Schedule for Observatory Park at Turner Farm
Public Viewing Sessions at Turner Farm in Great Falls, VA.
Scheduled Events:
Find all upcoming FCPA astronomy events here.
2026
| Date | Time | Title |
|---|---|---|
| Sat Feb 7 | 6PM - 8PM | Junior GS Space Science Investigator Badge |
| Fri Feb 13 | 7:30PM - 8:30PM | Night Sky Tour at the Roll-Top Observatory |
| Sat Feb 14 | 5:30PM - 8PM | Astronomy Festival |
| Mon Feb 16 | 4:30PM - 8:30PM | Scout Astronomy MB |
| Fri Feb 27 | 6PM - 7PM | Planet Adventure Night |
| Sat Feb 28 | 6PM - 7PM | Dark Sky Patch – Daisy & Brownie GS |
| Fri Mar 13 | 7PM - 9PM | Night Sky Viewing (Note time may change due Daylight Savings TIme) |
| Fri Mar 27 | 7PM - 9PM | Night Sky Viewing (Note time may change due Daylight Savings TIme) |
NOTE: Daylight Saving starts Sunday, March 8th.
Please check the Parktakes Activities/Events
Registration is Required (You may register at the Observatory Park Gate)
Fairfax County Park Authority maintains 4 telescopes in the Roll-Top Observatory for public viewing. In addition, we continue to invite the public to bring their own telescopes and set up outside the Roll-Top or bring their own binoculars for observing. There is a lot to see in the night sky.
These public observing sessions at Observatory Park are open to all, but you must register. Use the link to Parktakes registration at:
http://www.fairfaxcounty.gov/parks/parktakes/
- Use Direct Search
- Select Category of Activity SCIENCE AND TECHNOLOGY
- Select Place Turner Farm Park
- Click on Search Activities
These events are weather dependent. Check the FCPA Events Update. Our Observing Page also has sky weather updates. Wear appropriate clothing - nights can be very chilly. The Roll-Top observatory has an enclosed classroom, but the observatory room is not heated and is open to the sky.
Parking
If the parking lot is full, please use the overflow parking area.
Viewing
There are 4 telescopes set up for viewing in the Roll-Top observatory including a 7" high quality refractor.
For public sessions, we may also have telescopes set up outside the building along the walkway to look through. Members of the public are welcome to bring their own telescopes and set them up as well. If you bring your own telescope equipment and have not been at one of our public sessions before, we recommend you contact one of the volunteers first upon arrival so we can guide you on where to set up.
When you pull into the access road leading into the park, follow the road to the parking lot that will be to the left. Please put your headlights on low when entering the parking lot. All visitors must park in the parking lot. Enter through the pedestrian gate in the Northwest corner of the parking lot and follow the walkway up to the Roll-Top building (the squat building with the moveable roof). For public sessions, the Analemma Society will have a coordinator present to greet people and provide directions. But if the coordinator is busy or providing assistance inside the building, enter through the gray door on the walkway side of the Roll-Top building.
The public observing sessions and viewing events require registration. Be sure to register at http://www.fairfaxcounty.gov/parks/parktakes/ They are weather dependent, canceled if too cloudy or raining. Dress warmly as the observatory is not heated.
Note: We have had several requests asking about bringing their dog to the park. Dogs are not allowed into the Roll-Top or RATO observatories and classroom unless they are service dogs. Having your well behaved dog outside on a leash is allowed by the FCPA. Picking up after your dog is a must.
Note: Fairfax County Park policy: no alcohol or marijuana in the park. Thank you.
How large is our solar system?
We've all seen in books drawings of our solar system. The drawing of the sun, planets and moons, and the dwarf planet pluto all seem to fit nicely on the centerfold. Since the enlightenment, scientists have devised orraries to show the planets and their motions. But we're fooling ourselves.
The planets and moons are tiny compared to the sun and there is tremendous empty space between them. How much empty space?
Go to: https://joshworth.com/dev/pixelspace/pixelspace_solarsystem.html At the bottom of the window are tiny < and > scroll buttons and a small square slider to walk you from the sun to pluto. For the size of the sun (scaled so that our moon is one pixel on your screen) the length of the scrolling chart is 457 feet (139m).
Lost in space? Come to Obervatory Park at Turner Farm and walk from the gate to the Roll-Top Observatory. We've laid out the distance of the planets in real scale (but even then we've cheated on the size of the planets so that you can see them).
For Josh Worth's website, here is a cheat sheet for finding the planets (He uses the mean distance from the sun in kilometers).
There's a lot of empty space between. Try it on our walkway.
Venus - 108 million km
Earth - 149 million km
Mars - 228 million km
Jupiter - 778 million km
Saturn - 1.43 billion km
Uranus - 2.87 billion km
Neptune - 4.5 billion km
Pluto - 5.9 billion km
Circumzenithal Arc to End the Year
Dr. Jeff Kretsch frequents Observatory Park at Turner Farm and on the last day of 2023 took this photo of the sun's circumzenithal arc (sometimes called Bravais' arc) about 48 degrees from the sun, showing a rainbow of color. The arc (actually part of a circular halo) is created by plate-shaped ice crystals in the Cirrus clouds. The center of the arc appears to be at zenith (hence its name). For the sun angles to refract from the ice crystals to an observer on the earth, the elevation of the sun must be less than 32 degrees above the horizon. Note that blue is "on top" and red is "on the bottom". A normal rainbow created by water droplets has red on top.
NASA Astronomy Picture of the Day - 19 Dec 2023
One of our Analemma Society volunteers, Steven Powell, is a dedicated astronomical observer. In a recent email, he said, "I'm happy to say that my 32 hour exposure image of the California nebula [NGC 1499] will be displayed as the NASA Astronomy Picture of the Day on December 19th." You can find the full-size image on the NASA website: https://apod.nasa.gov/apod/ap231219.html At right is a small thumbnail view.
His photograph and hundreds of other spectacular views of the cosmos can be found in the NASA Astronomical Picture of the Day archive at: https://apod.nasa.gov/apod/archivepix.html
Analemma Society honored with FCPA Harold Strickland Partnership Award
The Fairfax County Park Authority awarded Analemma Society the 2023 Harold Strickland Award for Collaboration and Partnership for creating programming for Observatory Park visitors that minimizes or eliminates park bond funding. This award, https://www.youtube.com/watch?v=Xp3VeBj4P-8, is decades in the making with a growing number of patrons and programs.
In the past 5 years, Analemma Society has worked with more than 18,000 visitors at Observatory Park. Analemma Society volunteers donate more than 1,800 volunteer hours per year, fundraise for telescope purchases and maintain scientific equipment, as well as provide education and programs and festivals that teach science, technology, engineering and math through astronomy at Observatory Park in Great Falls, Virginia.
This year's ceremony featured a tribute to the vision and years of dedication of Analemma Society late founder Charles Olin https://www.fairfaxcounty.gov/parks/awards/ellydoyle. Fairfax County Park Authority Dranesville district representative Timothy Hackman presented the Harold Strickland Award to Christina Tyler Wenks, who accepted the award for Analemma Society and was also named an outstanding volunteer. The award was given to Charles's wife, Jacqueline Olin, as the couple founded Analemma Society and Observatory Park together.
More information about the Elly Doyle Awards and recipients may be found at https://www.fairfaxcounty.gov/parks/awards/ellydoyle. These videos were produced by Fairfax County Channel 16 and are shared with permission in celebration of the work of the many Analemma Society volunteers.
Passing of Analemma Founder Charles Olin
We are sad to report that after a period of ill health, Charles Olin, founding president of the Analemma Society passed away Tuesday night, March 28th, 2023. Without his vision there would be no Observatory Park. Charles and Jacque Olin were a powerful team that time and again accomplished things that seemed impossible. From a field of grass on the old Defense Mapping Agency and Nike site at Turner Farm, the concrete brick tower has become the Remote Astronomical Telescope Observatory (RATO), the dedication of a sundial garden, and through the Fairfax County Park Authority and a generous grant from the Edlemann's, we now have the Roll-Top Observatory and educational center.. Photo at right: Jacque and Charles Olin in front of the RATO, taken by TR Cook in 2013.
A memorial service was held at Observatory Park, Turner Farm in Great Falls, VA. for Charles on Sunday, May 21, 2023.
CHARLES H. OLIN (1933-2023)
Charles H. Olin was born in Niagara Falls to West Point Grad. Col. Charles L. Olin and Jeanette A. Olin. In youth he developed passions for arts, astronomy, and travel, crossing the ocean via ocean liner many times.
Charles received a B.S. in physics at Dickinson College, where he met his wife, Jacqueline: married in 1955. Charles was commissioned into the Marine Corps as a second lieutenant, studying advanced weaponry systems, leading tank maneuvers, and serving in the honor guard at 8th and I Marine Barracks, rising to the rank of captain.
Charles attended graduate school in Fine Arts at Cornell University, and then became one of the first students to attend the Art Conservation Center at New York University, Institute of Fine Arts. Charles was invited by the Smithsonian Institution to establish and develop multiple Conservation Programs for the Smithsonian. He was founder of the U.S. National Museum’s Conservation Analytical Laboratory (now the Museum Conservation Institute), The National Collection of Fine Arts Conservation Lab (now the Smithsonian American Art Museum Lunder Center), and the Conservation Lab at the National Portrait Gallery.
At the Smithsonian, Charles was responsible for conserving exhibits for two Museum openings, establishing analytical processes, and developing programs for training future conservators. He was among the founding members and a Fellow of the American Institute for Conservation.
After working at the Smithsonian Charles established a private conservation studio in Great Falls, VA: Olin Conservation, Inc. Charles’ company continues to serve numerous private, institutional, and museum clients across the country. During his own work in the private sector, Charles continued to train conservators, including a number of well-respected conservators in the field today. One of these is his son David. Charles was responsible for the conservation of innumerable works, including Renoir’s “Luncheon of the Boating Party”.
Charles considered his work in art conservation a "profession", rather than a "business." The key to his approach was observation, understanding, and attention to detail. These qualities were present in his lifelong passions. The study of science, specifically physics and astronomy, was omnipresent in every aspect of Charles's life. He was an avid gardener, naturalist, and he enjoyed the edible bounty of natural plants and wild game. Charles was a dedicated bow hunter and trapper. His love of classical music and opera was well known. Charles led championship teams with the Washington Area Dart Association and made wine from local vineyards. He enjoyed cooking. Charles was an accomplished sailor, including blue water adventures in his Hinckley Pilot 35, Betelgeux.
In Great Falls, VA, Charles became an EMT with the Great Falls Volunteer Fire Department. He was also the founding president of the Analemma Society at Observatory Park.
Survivors include wife, Jacqueline S. Olin, daughter, Dr. Deborah Norris, son David Olin, granddaughters Jessie Taylor and Jacqueline Hernandez, grandson Jon H. Norris, great-granddaughters Avery and Livia Taylor, and great-grandson Monte Taylor.
Simple Sky Observing
How to Find the Best Stuff in the Night Sky From Absolutely Anywhere
Atlas Obscura says it all very nicely in an article by Jessica Leigh Hester, with illustrations by Kristen Boydstun: Click -> Atlas Obscura - How to Find the Best Stuff in the Sky - Anywhere
Advice to New Observers
Ever wonder what telescope to buy? Refractor, Reflector ... Big Scope or a Little Scope ... Dobsonian Mount ... or maybe just a good pair of binoculars and a star catalog. As they say, this isn't rocket science. Here's an excellent article: So You Wanna Buy a Telescope - Advice For Beginners by Ed Ting. Ed walks through the type of telescopes and eyepieces and even the types of binoculars that will help you get started with a great view of the sky.
"The simplicity part is important...Beginners need early success, and the 6" or 8" aperture is big enough to throw up a bright image of most common celestial objects."