Innovative Astronomy Program for Camps, Part Two: Pipehenge

by Eric Jackson

The resident camp experience is about living away from home day AND night. All camps provide daytime activities and many do things at night — as we do at Carey Park. Astronomy is one of our nighttime activities. We have the big telescope, all the other necessary equipment, and a tame astronomer to take the sessions. But the weather always seems to obey Murphy's Law. Many nights were so disappointing that we often had to implement "plan B."

The Daytime Astronomy Program ("Innovative Astronomy Program for Camps," Camping Magazine, May/June 2004) was the breakthrough that changed all that. Sure, campers were enthralled with their shadow observations and related activities but when it was discovered that a nearby pipe climbing frame also cast shadows, a whole new idea was born.

The Origin of Pipehenge

A discussion with an astronomer, Frank Andrews from Carter Observatory, about the relationship between the movement of the campers' shadows and the climbing frame's shadow gave him an idea. He designed a structure for Carey Park's latitude — based on observing shadows, particularly solar noon shadows — to track the movement of the sun from sunrise and sunset between the shortest and longest days. We later discovered that it became an observatory at night.

Larry Randell, a friendly engineer (who did work for Education Board) rolled the steel pipes, and the camp maintenance staff welded them together.

There it stood — a 5 meter (16-foot) high walk-in sundial and observatory. Because it is made of steel pipes it was dubbed with the nickname, Pipehenge.

Pipehenge provided us with two complementary activities for daytime and nighttime. Because no one had ever used a "Pipehenge" before, staff and campers soon began to make exciting discoveries extending from their daytime observations.

So impressed were school teachers who worked with Pipehenge at Carey Park, many asked about getting one for their schools. Education boards were unhappy with the height of the structure so Randell redesigned it to meet our public school safety standards and refined them to reduce costs. Because a Dedicated Site Pipehenge is also an observatory, it must be designed for the latitude of the particular school or camp, which makes it impossible to mass-produce or supply plans for the Pipehenge. For more information about the project or if your camp is interested in getting a Pipehenge, contact

So What Is So Special About Pipehenge?
Dedicated Site Pipehenge at Rainbow Christian Camp
All the pipes are colored, named (with labels), and are astronomically significant. Refer to the photo of the Pipehenge on page 36. A brief description of each pipe is listed below:

  1. Navigator's Seat is the central point of Pipehenge. From here, campers make their observations as the navigator. A compass rose is imprinted into the seat.
  2. Circle marks the path of the Little Dipper as it appears to the navigator, to revolve around the North Celestial Pole.
  3. Ring (not labeled) marks the North Celestial Pole, the point in the sky above the North Pole, around which the earth turns. Northern sky stars appear to revolve around this point.
  4. Star Bars (not labeled) may be used to measure the rotation of Northern sky and stars at night.
  5. Summer Arc (Tropic of Cancer) is the path the sun follows on the longest day of the year (June 21).
  6. Meridian is the pipe that is aligned true North to South and is the “division” between East and West and a.m. and p.m. When this pipe is on the sun, it is the middle of the day — or solar noon local time.
  7. Winter Arc (Tropic of Capricorn) is the path the sun follows on the shortest day of the year (December 21).
  8. Horizons are pipes that represent the eastern and western horizons from the viewpoint of the navigator. They show the changing positions of sunrise and sunset throughout the year.
  9. Compass points are the four vertical legs of Pipehenge and are placed at the cardinal points of a compass — as marked on the navigator’s seat.

Pipehenge on the Move

My science consultancy work for the Auckland Education Board include running camp programs for their six hundred schools. This gave me the opportunity to present papers at New Zealand and Australian science teacher and camp conferences. After demonstrating a large modular Pipehenge at a Camping Association of Victoria (Australia) conference, I was asked if I would do the same for a Boy Scout Jamboree. Three Pipehenges were set up along a North/South line through the jamboree campsite — and two thousand Boy Scouts did practical work for their compass and navigation badge and astronomy badge.

The Evolution of Pipehenge

Boy Scout Leaders were so impressed with the concept that they asked if it was possible to make a portable version that could also substitute as the frame of a two-man tent. When this was done, it became easier to take the portable version to other conferences. So the Pipehenge concept was introduced at various science teacher and astronomy conferences in the United Kingdom, Canada, and the United States — and was a central exhibit in the foyer of the hotel at the International Camping Congress in St. Petersburg, Russia, in 1997.

At a New York State science teacher's conference, teachers commented that if the portable Pipehenge could be made so that it is adjustable to any latitude, it would then work well in their science programs. So we went back to work and made an adjustable version that has greater appeal to high schools than the larger climbing frame version. Some camps are purchasing the portable Pipehenges because they can be set up at different locations.

An eleven-year-old Samoan boy made a model of the large Pipehenge from coat hanger wire. I was so impressed with the idea that I made one myself and used it for display purposes to show its application to technology. Science teachers who saw it were enthusiastic, seeing its potential for teaching astronomy. Earth science teachers suggested that if class sets of these were available they would be useful for laboratory work in senior physics classes. Randell came up with the idea of combining a globe and the wire frame, so a tabletop version, the Earth Space Simulator (ESS) module was developed.

The climbing frame versions (Dedicated Site Pipehenges) continued to be installed in schools and camps as a teaching aid for day and night activity — and as a piece of recreation equipment. As one camp director said, "If they don't know what to do with it at least they can climb on it."

A Dedicated Site Pipehenge is:
A walk-in sundial. The pipes create shadows on the ground, which move throughout the day and year.
A calendar. Plotting the length of shadows throughout the year relates them to seasonal monthly changes in the environment and in the sky.
A compass. Set out on a North/South alignment is the start of working with compasses and orienteering. The navigator’s seat has a compass rose imprinted on its surface.
A globe of the Earth. Pipehenge basically is a skeletal framework of a globe designed for the latitude where it is installed.
A spaceship. A camper sitting on the navigator’s seat in the center of the structure can be regarded as sitting in "Spaceship Earth" viewing the solar system through the "windshield" between the summer and winter arcs.
An observatory. The pipes form a grid for nighttime observing of the paths of the moon, planets, and constellations seen from the latitude of the camp.
A climbing frame. The shape of the structure offers a challenging climbing frame for campers and upper limb activities for campers in wheelchairs. The very first Pipehenge that was sold went to a school for visually impaired children who used its shape and temperature variation of the pipes on a sunny day in an attempt to teach the changing effect of the sun.

When Rod Cameron, the director of Rainbow Christian Camp in Converse, Indiana, visited Carey Park, he was so impressed with our Pipehenge he said that if he ever had enough money he would get one for his camp. When a family with long association to the camp wanted to donate a piece of equipment in memory of their happy times there, Rod knew what it would be, the Pipehenge!

The Wonder of Pipehenge

As well as being a hands-on teaching aid, Pipehenge is also a research project. Our campers undertake observations and studies that are networked internationally. At Carey Park we have developed comprehensive daytime and evening activities for the three Pipehenge modules for campers and schools using our facilities.

Pipehenge is proof that what may start out as a seemingly insignificant idea can develop into a piece of equipment and a learning concept that has worldwide appeal. This happened because our camp staff saw its potential, developed it, and demonstrated it in a range of forums. And we continue to refine and extend Pipehenge's applications as others contribute their suggestions and ideas.

To be astronomically accurate, a Dedicated Site Pipehenge must be designed for the latitude of the camp. This provides a frame of reference whereby the principles of astronomy are able to be taken as daytime activities — using observations of the interaction of the nearest star (the sun), nearest planet (Earth), and nearest moon (our moon). These give understanding of the movement of planets, apparent solar movements, day and night, eclipses, moon phases, tides and seasons — and enables campers to observe and record changing daily and seasonal movements of the sun between its solstices and the effect that this has on the local environment. At night the structure becomes an observatory.

Pipehenge must be installed on a line from the North to South geographic poles through the camp (its longitude). This means that it functions as a compass identifying East and West, as well, and brings attention to the difference between true and magnetic poles. Four vertical pipes are at the cardinal points — North, East, South, and West. Because it is aligned true North/South, it identifies the meridian for the camp. Looking South, the left half of the structure is East and on the a.m. (ante meridian) side of the meridian. The right side (West) is the p.m. (post meridian) side. At solar noon, local time, the meridian is on the sun and all shadows point to the North Pole. The shadow of the South, meridian, and North pipes is in a straight line along the ground at solar noon. Positioned on the eastern and western sides are the horizon pipes along which the sun rises and sets progressively throughout the year between summer and winter solstices. Campers are amused to learn that these horizon pipes are six months long.

Pipehenge is also a skeletal globe of the earth designed for the camp's latitude. The Tropics of Cancer (Summer Arc) and Capricorn (Winter Arc) are marked by curved pipes joining each end of the horizon frames and mark the band of the sun's path across the sky between its solstices (the longest and shortest days). This path is called "the plane of the ecliptic" as seen from the camp's latitude and is the path in the sky along which campers will find the moon, planets, and constellations of the zodiac. The lengths of these pipes represent the hours and minutes of daylight, for mid-summer and mid-winter at camp. Through these activities the calendar attribute of the structure is observed as the seasons change.

Looking North from the navigator's seat, a pipe circle marks the path of the Little Dipper and other circumpolar stars. A ring in the center of the circle marks the North Celestial Pole through which the Polaris is seen at night. Pipehenge is spaceship earth. The seat in the center is the navigator's seat (the optical center) and the point from which campers make most of their observations and may take nighttime photographs, looking North, to show the concentric paths of circumpolar stars.

Eric Jackson is the chairman of Carey Park Christian Camp in Auckland, New Zealand, and has had extensive international camp leadership experience. Until his recent retirement, he was district science adviser for the Auckland Education Board's 600 schools and was responsible for science curriculum development, teacher in-service training, and the development of Education Outside the Classroom programs, particularly those that relate to camps. For more information, contact Eric at

Originally published in the 2005 May/June issue of Camping Magazine.