Eight Decades of Amateur Telescope Making in the DC Area
Channel: Northern Virginia Astronomy Club
Date: 2022-11-15

Only via the art and craft of telescope making are you able to make an object that is accurate to within a small fraction of the wavelength of light, with just your bare hands and some simple, hand-made measuring devices, without an enormous budget, and have it work extremely well. Even though much of the science of optics is well beyond the ken of most people, the math needed for making a Newtonian is mostly what one learns in high school algebra and trig.

This talk will reflect on the history of telescope making in the DC area beginning in the late 1930s through present times.  I’ll describe my involvement with the Chevy Chase Community Center in DC, one of the few remaining centers in the country that hold amateur telescope making classes.    Best of all the instructional classes are still free, and probably worth at least twice as much as that! 

The workshop at Chevy Chase has excellent facilities for anybody who wants to either build a telescope from scratch, or test their existing optics, or modify or fix what they already have. Our facilities include metal and wood lathes, a powerful Chinese mill-drill, and a SawStop table saw, and both metal and wood band saws. We also have a wide variety of hand and power tools; lots of donated paint; assorted metal parts like nuts, bolts, springs, and washers; a variety of measurement devices; and an optical testing tunnel with a variety of testing rigs. In addition to raw mirror blanks from 3 inches up to 18 inches, we also have abrasives, pitch, and grinding tools – and a few completed mirrors that need to be put into telescopes.

Join us and learn about telescope making, how far we’ve progressed since the 1930s, and what the future might hold for this art and crafts form of amateur astronomy.

Biography:

Guy Brandenburg has been volunteering to lead the telescope making classes sponsored by the National Capital Astronomers for about 20 years.

A DC native, and a graduate of Dartmouth College and the University of Maryland, he taught secondary math at various levels to DC public school students for over 30 years, before retiring in 2009. Among other things, he coached highly successful middle-school-level MathCounts teams at two different DC junior high / middle schools, and for about a decade was also the lead teacher in a hands-on Saturday science academy for middle schoolers run by the Carnegie Institution for Science at their P Street headquarters.

He is currently the president of perhaps the second-largest DC area astronomy club, National Capital Astronomers, and is a long-time NOVAC member. He is also the current president of the Hopewell Astronomical Society, which built, owns, and operates a small private observatory of the same name atop Bull Run Mountain, near Haymarket VA.

He recalls his parents showing him Sputnik’s booster in the dark night skies of the family farm just outside Clarksburg MD back in 1957, and watching amazing auroral displays in northern Vermont from the farm he was renting in 1972. He also took an astronomy class in junior high school and in college. But he never owned a telescope until he built one, including the optics, under the guidance of the late Jerry Schnall at the same workshop where he now volunteers. For his first scope, he used a design in Richard Berry’s book on making your own scope, which he got from a science-oriented book-of-the-month club. He has lost count of the number of telescopes he has built or helped others to build since then, and he has modified that 6” f/8 scope twice in order to take it by airplane to view eclipses in Chile (1994) and Wyoming (2017).