From the classroom to the end of the galaxy - School students build telescopes in Israel

By Eden Orion posted 09-03-2021 09:55


It all started over thirty years ago. I read the book "Black Box" by Amos Oz.

The book describes a letter exchange between a pair of divorced parents Alexander and Ilana. Their son - Boaz, is in the gaping abyss.

Boaz finds a part of his wandering soul between his two parents in the construction of telescopes. In some of his letters to his father he asks him to purchase and send him components for telescope making from the United States. In some letters Boaz tell his father little about the practical knowledge he acquires in the field of optics. Of course, this is not the essence of the book and, to be exact: It is all about a page and a half. These lines, however, convinced me that the writer Amos Oz, must have done some research on the subject, and that there are People in Israel who build telescopes.

I found out about the amateur community of astronomers in Israel (their numbers are quite limited…) and I  was told about Yossi Khoury, the founder of the “Haparvarim” duo, who, as he plays guitar and sings wonderfully, builds even more wonderful telescopes ...

Yossi received me very kindly in his home and I learned a lot from him about building telescopes. At the same time, I purchased several books and eagerly "swallowed" them.

What I was missing was a workshop. A place, equipped with tools, and an area where I can begin to realize my dream.

In late 2002, I found a workshop. It was the sculpture workshop of the Department of Fine Art at the University of Haifa where I studied.

I convinced the sculptor, (Israel Prize laureate) Jacob Dorchin, that I would build a sculpture of metal, wood and glass and eventually look through it to the stars. To my surprise, he agreed and so I set off and built the first telescope.

The following year, I built two more telescopes and all three of them were featured in the graduation project followed by an exhibition at the Tel Aviv Artists House Art Gallery.

Immediately at the end of my studies I began to make public observations using the telescopes I built, some of them initiated and some of them along with other astronomy enthusiasts who would come to the town square and allow the visitors to see the various sky elements. Some viewers were thrilled beyond watching the various elements of the sky by the fact that they were watching through a hand-built telescope. Here and there, questions began to arise as to whether children could be taught to build telescopes.


I researched the subject and found out that there are many clubs in the United States where telescope Making  and mirror grinding is popular practice . Moreover, I learned that polishing mirrors is an action that requires a great deal of time and patience, and doing it by girls and boys gives them important tools in for life (patience, precision) beyond experience in optics and construction.

The construction of telescopes, beyond the manual work, requires the application of basic principles of physics, geometry and Mathematics that are commonly taught in schools.

On the other hand, there is a saying among all the telescope Makers in the world that says: It Ain't Rocket science, or in words, this is a task that almost anyone can meet.

I started looking for partners in Israel. I met with teachers, principals and school administrators, supervisors, lectured at conferences, all of which sounded very willing to an area that combines practical application of theoretical material learned in classrooms with hands-on work in the field of carpentry and integration of other materials. Cross curriculum at its best!

In most cases, the enthusiasm went off as we started talking about an actual implementation of the thing. Whether this involved barely raising budgets, or unwillingness (sometimes with the excuse of insurance) to take responsibility for students using power tools. These search campaigns for talk partners lasted over ten years until I met Amir Harpaz.

Amir, a fighter pilot,  who, after filling a long line of senior positions in the Air Force, decided that his place in the education system was appointed to run the Misgav regional school. Amir, who also taught physics while running the school, met me in one of the public observations I made, and together we decided to realize the dream that Children will build telescopes.

In cooperation with the Misgav Regional Council, a meeting with a representative of the IAC Foundation was convened and, after detailed explanations, the green light (and donation accordingly) was allowed to start.

To manage the project on behalf of the school, Dani Ovadia, an outstanding teacher and a great deal of seniority in physics teaching, was selected. Danny enlisted science teachers in the junior high, and as the head of the Local Culture Center, was also geared up for the physical construction of the workshop.

The culture centres buildings in Israel are identical, and include in one building an auditorium, halls for circles such as dance and craft, classrooms and labs and also… a balcony.


Because the sun in Israel is so hot there is almost no usage of balconies so it was decided to close the balcony with walls and windows. The covered and enclosed area is divided into two classes:

A class for modern agriculture and a class that also contains an astronomy study workshop - where the telescopes will be built.

At this point I prepared a detailed list of required equipment for the workshop and at the same time a list of everything needed for the construction of four telescopes.

Because the number of hours I was allowed was limited - four sessions each, precise and detailed planning was required for what to do at each lesson and each step, as well as ordering most of the construction materials for the telescope to arrive at the correct dimensions and meet the tough schedule on the other.

The equipment arrived, the optical components ordered from the United States also arrived and I needed a type of "importer's license" to release them from customs. everything was ready for the students to arrive.

The big day has arrived. Early in the morning, students from both groups came in for an introductory lecture. They heard about the Newtonian telescope, saw various telescopes created by Newton's design and finally the workshop and stages were described.

At noon that day, first-class students re-entered the workshop. After reading safety instructions and distributing goggles, we got started. Those students, most of whom did not go hand-in-hand and certainly not in electric-saw, got the job started straight from cutting the telescope without prior training. At first they held the saw together with me or with the extra teacher. The following sawing has already been done alone.

Later, the students met the Compass. After brief explanations of the use of the compass and the difference between radius and diameter, they sketched the circles on the wooden boards, and managed to cut the wooden circles!

Then when all the base parts were in their hands and after grinding their edges, their adhesion time reached the base of the telescope. Toward the end of the lesson, two proud telescope stands were already standing on the desks.

In the second session, the students began to build the telescope tube. For the first time in their lives, they were required to use a drill press to drill holes (perpendicular to the plane) and from there with the saw to perform a more complex and gentle circular sawing than the previous encounter. The adhesion task required a great deal of accuracy (up to a millimeter) and the students used a metal right angle to check the correct perpendicularity of these parts relative to the other.

At the end of the second session, the telescope tube boxes were ready, with the exception of one end to be made at the last meeting after assembling all optical parts.

The third meeting is entirely dedicated to connecting the optical parts of the telescope.

At the beginning of the session, students assemble the main mirror holder. The installation consists of one of the discs remaining from the previous lesson's telescope sawing, and a pre-made square rear end. Both of these brackets are connected by means of bolts and springs (disassembled from door holders) that will later be able to adjust the mirror angle optimally.

Then they drilled a hole for the Focuser, at a point that was calculated according to the mirror data. After drilling, the focuser facility will be connected using screws and nuts.


Above it, the "spider" consists of a metal cross in the center of which is attached the secondary mirror, also by means of screws that allow its precise tuning.

At the end of the session the main mirror is affixed with silicone to the main mirror holder.

Fourth and final session: Last assembly and Calibration.

At the beginning of the session, students connected the mirror cell (with the mirror ) to the telescope tube. after checking that all the screws of the focuser device and secondary mirror are securely attached. The top cover of the tube is fastened with wooden screws, unlike the adhesive, so that in case of a malfunction, it is possible to remove and reach each of the internal telescope parts.


Next, the alt wheels used for the alt bearings will be fastened and the bolt used for the Az bearing shaft will be attached.


The telescope is ready.

It must now be calibrated with a "laser collimator" with this device and with the adjusting screws that we have made on the main mirror cell and in those which are mounted in the secondary mirror holder, the direction of the light rays on the "same axis" can be accurately tuned. The process takes minutes and the students do it in pairs.

At the end of the process, the telescopes are taken out of the classroom, locate a distant tree top, point the telescope at it, and begin to rotate the focus knob until a clear image is obtained. This is the practical test that the telescope is working properly.


Of course, the telescope's examination with the sky is done at night when there is a moon and stars. 

News from all over the globe about a strange pandemic was in the air and there was a rush to make the last event for the children and the parents before the state went into closure...

The telescopes were taken to the Culture Center square where we had a nice view of the sky and the telescopes were pointed to the moon.
The students came with their proud parents to test the telescopes for the first time.

It is a pity that voices (not to mention shouting) cannot be conveyed in writing from the throats of the students and parents that they see the craters, mountains and seas on the moon, using their self-built device.

Here is a short movie that conclude the whole thing - Enjoy

1 comment



09-08-2021 09:35

Your story  is wonderful and thank you for sharing it! Your students did a fine job of making the telescopes and hopefully they will be able to use them again soon.