January 2001 Newsletter

Stockton Astronomical Society

Valley Skies

Valley Skies - January 2001 Issue

The Telescope Nut
by Jeff Baldwin

High School ATM

Amateur Telescope Making is alive and well in public schools. I'm lucky in that I get to teach an astronomy class at my high school, and part of that class is ATM. Here's the story:

Way back around 1991, Mark Miller, a chemistry teacher at East Union High School in Manteca, asked me to come up with a plan to build a 4.25" f/8 telescope that could be replicated twenty-five times for a class set. We built one in my garage, and he took the design back to his class and they copied it for a class set. Then those high school kids went around to the middle schools and did all-night astronomy with 6^th graders. That project finally went away, and the telescopes were stored at the Manteca School District's warehouse.

Years later, I found out that they were still around, and the district let me have them all for my astronomy class, which I teach at Sierra High School. They were filthy and in total disrepair. Furthermore, the wrong secondary mirrors were installed and were too small to reflect all the light from the primary mirror. Neither mirror could be collimated and the altitude bearings were bolts in holes.

I turned those telescopes into a class project. They needed to have the new larger secondary mirrors installed, new spiders made, focusers relocated, tubes cleaned and painted, primary mirror cells rebuilt so they could be adjusted ... and they had to work.

When kids tear apart a telescope and put it back together, they have a better understanding of how it works, how to collimate it, how to fix glitches that occur while observing and how to make it more stable and efficient. They worked really hard to make those telescopes into useful instruments. The students took the finished telescopes home on a check-out basis and are using them to observe the Moon, Jupiter, Saturn, Venus, clusters and galaxies, nebulae, and of course, neighbors.

We are also building a 10" scope. It will be completed eventually, but it is going pretty slowly. That's okay. The work to create it is as rewarding as using the telescope itself.

A group of students frantically disassembling a Dob, like sharks in chum.

Sometimes spiders can be really difficult. Both these students were very patient with their projects.

Polishing mirrors at school. It takes a lot of time rubbing glass to bring it to a total polish.

Some of the students go out on their own in telescope building. Leo Radcliff, an SAS member, is an alumnus of the SHS Astronomy Class. He and his father Roger are building an 18" BVC mirror. Matt Rennie is also an SHS Astro alumnus.

Next year I plan on having the 10" scope finished, the tubes replaced for the 4.25" scopes, and a set of more stable bases built.

Hopefully some of these kids will become amateur astronomers, or more!

Clear Glass...Jeff Baldwin
For more information on Telescope Making jump to the ATM page.


Sometimes spiders can be really difficult. Both these students were very patient with their projects.	Polishing mirrors at school. It takes a lot of time rubbing glass to bring it to a total polish.