Clearing disinformation is our first job at the Telescope Makers’ Workshop. “So you’re grinding a lens!” No, we’re grinding a mirror. “How do you put the coating on the back?” The aluminum coating actually goes on the front. In that sense, it’s not really a mirror, it’s a mirror holder! “That mirror you’re making; what power magnification is it?” The mirror doesn’t magnify anything. The magnification is done by the eyepiece; the mirror just gathers enough light to make the view worth looking at. “Will it save me money?” Well, probably not; but amateur astronomy is rarely about saving money or time.

Make Your Own Masterpiece

Held every Friday night at Oakland, California’s Chabot Space and Science Center, the Telescope Makers’ Workshop is an informal gathering where you can learn how to grind and polish a high-quality Newtonian telescope mirror and, hopefully, turn it into your own masterpiece of optics, woodcraft, and design. We have helped build thousands of telescopes over the workshop’s 70+ years of existence. A typical project takes a year; the largest we’ve seen someone build is 22 inches. Every person’s telescope is different, albeit they all work according to the same optical and mechanical principles. The accuracy of your work is measured in millionths of an inch!

Building a telescope involves a unique combination of physics, mathematics, astronomy, and craft. You don’t have to be a rocket scientist, but you might just imagine you’re flying in a rocket as you look through your home-built scope and see galaxies, clusters, and nebula invisible to the naked eye, inhabiting regions of space thousands or even millions of light years from planet Earth.

Aim for the Stars

The workshop is free to the public, and funded by the Eastbay Astronomical Society. Students have to purchase some materials and scavenge the rest, but the Society provides grinding and polishing compounds as well as instruction and measurement. Visit their website, or check out the Eastbay Astronomical Society, for more information about getting started.

More Telescope Workshops

Look online for a telescope workshop near you — standouts include the Springfield Telescope Makers in Stellafane, Vermont, the National Capitol Astronomers in Washington, DC, led by Guy Brandenburg, and Dave Frey’s workshops with the San Francisco Amateur Astronomers.