Through the Fairfax County Park Authority Parktakes courses, you can take an introductory course on telescopes, learn about the Moon, or you can learn about the physics of meteors ("shooting stars") and techniques to observe them. The courses will be given at Turner Farm - Observatory Park in the new Roll-Top Observatory.


The Parktakes Turner Farm Park Astronomy courses will be held whether it is clear, cloudy, or raining. All of the courses have a presentation and talk segment. The observing portion using the Roll-Top Observatory will be held to the extent permitted by the current weather conditions.


Date/Time                                Title                                                                           Ages

Sat   1/06/2018 10:00 AM       Rainbows, Haloes and Glories                                      6-Adult - Geared for the Family

Tue  1/09/2018 7:30 PM         Introduction to Telescopes                                            6-Adult - Geared for the Family

Sat   1/13/2018 4:00 PM         Astronomy Festival                                                       3-Adult - Geared for the Family

Wed  1/17/2018 7:30 PM        Rainbows, Haloes and Glories                                     9-Adult -  Geared for the Family


Sat   2/10/2018 10:00 AM        Radio Astronomy - Listening to the Universe               9-Adult - Geared for the Family

Sat   2/17/2018 4:00 PM         Astronomy Festival                                                       3-Adult - Geared for the Family

Sat   2/24/2018 11:00 AM        Meteorites: Exploring Visitors from Space                   9-Adult - Geared for the Family


Tue   3/06/2018 7:30 PM         Introduction to Telescopes                                           9-Adult - Geared for the Family

Sat    3/10/2018 10:00 AM       The Marine Sextant                                                     9-Adult - Geared for the Family

Wed  3/14/2018 7:30 PM         Astronomical Seminar & Telescope Viewing               9-Adult - Geared for the Family

Sat    3/17/2018 4:00 PM         Astronomical Festival                                                   3-Adult - Geared for the Family

Tue   3/20/2018 7:30 PM         Family Fun Night and the Telescope                            6-Adult - Geared for the Family

You can register at:   All it takes is the sign up with Parktakes to get a member number, locate the course registration page and provide a valid email address and Visa or MasterCard.

Course Descriptions:

Astronomical Seminar and Telescope Viewing:  Instructors Analemma Society Staff

RT Telescope SingleThe Roll-Top observatory at Turner Farm will hold a classroom seminar and nighttime observing session focused on a specific astronomical topic each month.  The topics will range from planets, open clusters, double stars, stellar color spectrum, globular clusters, and galaxies.  Telescopes will be used to view the objects of the month discussed in the classroom (weather dependent).  Check the Analemma website for monthly topics ( 


Intro to Telescopes:  Instructors Analemma Society Staff

Now that you have received a new telescope, how do you set it up and use it?  Or are you considering buying a telescope?  This course goes into introductory basics of Astronomy, observing the sky, and what you need to know to setup and use your telescope.  Will provide hands-on use of telescopes and observing selected objects in the sky using the Roll-Top Observatory if the weather allows it.  Attendees can bring their own telescope for assistance and advice. (Conducted throughout the year)


Meteor Astronomy:  Instructor Peter S. Gural (Senior Scientist, Leidos)

Fireball 557x398Couse covers basic meteor astronomy including meteor phenomena and when they can be seen, fireball reporting and simple visual observing techniques.  Learn about automated observations using affordable video cameras.  Course also covers advanced techniques using radar, radio, infrasound and spectroscopy.  Optional outdoor visual observing sessions after class weather permitting; bring a lawn chair and warm cover/sleeping bag. (Conducted Tuesday 12 December at 7:30 PM)


Meteorites: Exploring Visitors from Space  Instructor Cal Powell

What are meteorites? Where do they come from? What do they tell us? This course is an introduction to these visitors from outer space, suitable for children and adults. Participants will have an opportunity to touch and examine actual meteorites including specimens from the Moon and the planet Mars. The course will be held in the Roll-Top observatory classroom at Turner Farm Park. (Conducted , Saturday February 24 at 11 AM)


Moon Gural 300x188Exploring the Moon: Instructor Bill Burton

The Moon is as old as the Earth, and its surface is marked by craters and lava flows billions of years old.   Explore these lunar features through a high-powered telescope and learn about their origins.   See where the Apollo lunar landings occurred, and discuss what the astronauts found.  Class will meet rain or shine with alternate viewing sessions available for cloudy days. 


Family Fun Night at the Telescopes:  Instructors Analemma Society Staff

Wondering about the earth in space and the kinds of strange objects that make up our universe?  Then join our family introduction to Telescopes in the Roll-Top Observatory at Turner Farm Park and take a personal guided tour of the heavens and see the color of stars, open and globular clusters, nebulae and galaxies with your own eyes (dependent on the weather).  No experience required. 


AstronomyCourse Roll Top2017Astronomy for Family Fun: Various    Instructors TBD

Enjoy hands-on activities and looking through our telescopes to learn about the solar system and everything in it. Explore every corner, observe some planets (dependent on the weather), and find out why Earth is just right to support life.  (Conducted September 28 - Solar System)

Enjoy hands-on activities and looking through our telescopes to explore the universe (dependent on the weather) and learn about mind-boggling phenomena and celestial happenings. A different topic each night:  (Topic for December 7: Geminid Meteor Shower)


Rainbows, Haloes and Glories  Instructor Jeff Kretch
Rainbow trimThe January Astronomical Seminar will cover common and some uncommon phenomena people can see in the open sky such as rainbows, haloes and glories. Sunrise and sunset phenomena like the green flash, the purple light, and simple questions like why the sky is blue and why sunsets are orange are also covered. The seminar will teach people how to better appreciate the sky both day and night. There will be an observing session in the Roll-Top Observatory after the presentation if the weather allows. (Conductedt Wednesday, January 17 at 7:30PM )



Radio Astronomy: Listening to the Universe  Instructor Robert Kellogg, Ph.D. 

Jupiter IoWhat can you hear from space? Join the adventure to understand cosmic noise and what it tells us about the sun, the magnetic structure surrounding some of our planets (and the strange radio signals from Jupiter and its moon Io). Then learn how our galaxy is mapped using the faint signals from hydrogen atoms and the behavior of molecules. Little green men? That was one of the possibilities of the strange sounds of pulsars, strange dense fast rotating stars. Come hear what our universe is saying. Course will be held in the Roll-Top observatory classroom at Turner Farm Park. (Conducted Saturday, February 10 at 10 AM)


Introduction to the Marine Sextant 

The marine sextant is the instrument used at sea for the purpose of establishing a ship’s position by observing the altitude of a celestial body above the horizon. Become familiar with the working parts of a sextant and learn about the proper care and storage for this precision instrument. Demonstration sextants will be available to examine first hand. The course will be held in the Roll-Top observatory classroom at Turner Farm Park. (Conducted Saturday March 10 at 10 AM)


HistoricMarker SignOn June 24, 2017, a bright Saturday morning, Fairfax County Park Authority and the Analemma Society hosted the dedication of the Historical Highway Marker Nr, 143.  Clyde Smith, Chairman of the Virginia Department of Historic Resources Board explained that obtaining one of these markers on the side of the road requires quite a bit of effort to ensure accurate historical significance.

The area today known as Observatory Park at Turner Farm led a pivotal role over nearly three quarters of a century.  In 1954 a portion of the Turner Farm became a Nike missile site, along with a ring of other sites, to protect Washington D.C.  As the missiles became obsolete, the grounds were turned into a facility for the U.S. Army Map service for geodesy and navigation.  In 1961 the U.S. Army Map Service initiated a significant satellite tracking program that became part of the Defense Mapping Agency in 1972 and more recently became the National Geospatial Intelligence Agency (NGIA).



GRAB 1 and Transit 2A

NRL Galactic Radiation Background (GRAB) Satellite 
and JHU-APL Transit II-A Navigation Satellite
carrying first "digital clock" June 22, 1960

The Fairfax County Park Authority, Analemma Society and Great Falls Library have teamed up to present a two-part lecture series, “From Sundials to Satellites to GPS,” on April 6 and May 4, 2017. Talks will be held in the library’s meeting room from 7 to approximately 8:30 p.m.

On April 6, Stephen Malys of the National Geospatial-Intelligence Agency will speak on the topic “Journey to the Center of the Earth-Status of the Terrestrial Reference Frame.” The program will review progress in the past 2,000 years in charting earth’s measurements, starting with the age when sundials and trigonometry were considered high tech.

On May 4, Paul Ceruzzi of the Smithsonian Institution’s National Air and Space Museum lectures on “Not just GPS: Why Russians, the European Union, China, and India are building satellite navigation systems, and what that means for the U.S. Global Positioning System.” Ceruzzi will give a brief history of GPS and show how it has grown far beyond the expectations of its creators.

The lectures are free, and no registration is required. Participants are invited to attend one or both talks. This program ties into activities at the Park Authority’s Observatory Park at Turner Farm. The International Sundial Garden at Observatory Park is part of the Turner Farm Conceptual Development Plan and the first sundial, the Jamestown Commemorative Sundial, was installed in 2007. The Army Map Service/Defense Mapping Agency activity that was at the site from 1963 to 1993 was a Satellite Tracking Branch whose work was important to the development of GPS.

Great Falls Library is located at 9830 Georgetown Pike in Great Falls, VA. For more information about the lecture program, contact Daniela Dixon at 703-757-8560.  DOWNLOAD THE FLYER

Download this file (GPS-Sundials-Flyer3.pdf)GPS-Sundials-Flyer3.pdf[ ]125 kB

roll top dedication oct 2016 450pxAmid the rain and cloudy skies, on Saturday October 1st, 2016, a ribbon-cutting ceremony officially opened the Roll-Top Observatory at Observatory Park, Turner Farm in Great Falls, VA. Tim Hackman, Dranesville District representative of the Fairfax County Park Authority (FCPA) Board, introduced all those who made the Roll-Top observatory possible through public-community-and-private funding. Initiated in 2007 in collaboration with the Analemma Society, the million-dollar facility was funded in part by the 2008 and 2012 Park Bonds, telecommunications funds, Mastenbrook grant money and a donation provided by Jean and Rick Edelman through the Fairfax County Park Foundation.

Ground breaking for Roll-Top began in 2014 and over the next two years the Roll-Top Observatory design by architects Shaffer Wilson Sarver & Gray of Herndon, VA, was carried out by the construction company Brown and Root of Arlington, VA.

Inside the Roll-Top Observatory a plaque was unveiled stating that the telescopes are made possible through the generosity Jean and Ric Edelman and members of the Analemma Society. 

roll top dedication Olins Edelmans 450px

FCPA logo colorCome join the Analemma Society  and the Fairfax County Park Authority on Saturday Oct 1st, 2016 at 10am when the FCPA will dedicate the Roll-Top Observatory and Classroom.  The dedication will be at Observatory Park of Turner Farm Park at 925 Springvale Road in Great Falls Firginia.  For more information, contact the Public Information Office of FPCA at 703-324-8662.

Roll Top Construction 2016 09 10