Astronomy popularizer John Dobson dies

It’s a sad moment for amateur astronomy. The San Francisco Sidewalk Astronomers (SFSA) reported yesterday the passing of John Dobson. He died peacefully Wednesday morning, January 15, in Burbank, California. He was 98. He leaves behind a son, numerous close friends, and fans and admirers worldwide.

Dobson is best known for inventing a revolutionary mount for reflecting telescopes. Now known as the Dobsonian mount, it is an altitude-azimuth assembly that is both simple and inexpensive to build. And although he also taught telescope making — including how to grind and polish mirrors — the benchmark moment came when he devised the mount.

During the past four decades, uncounted thousands of observers have Dobson to thank for letting them enjoy views of the heavens through larger (and often much larger) telescopes than they could have afforded prior to his invention.

Dobson was born September 14, 1915, in Beijing, China, where his maternal grandfather had founded Peking University in 1898. The family moved to San Francisco in 1927. 

Dobson graduated from the University of California, Berkeley, with a master’s degree in chemistry. Afterward, he worked in the corporate arena for only a year.

In 1944, Dobson joined the city’s Vedanta Society monastery. There, he spent 23 years as a monk of the Ramakrishna Order. He saw one of his tasks as reconciling astronomy with the society’s teachings.

Dobson built his first telescope — a 2-inch refractor — in 1956. He used a lens he purchased in a junk store and an eyepiece from old binoculars. Through it he saw the rings of Saturn.

One of his fellow monks mentioned that it was possible to grind a mirror and construct a reflecting telescope. Dobson quickly made his first mirror out of a 12-inch piece of porthole glass from a marine salvage yard. When he looked at the Last Quarter Moon through his finished scope, he was surprised and deeply moved by what he saw. His first thought was, “Everybody’s got to see this.”

In 1958, the order transferred Dobson to the monastery in Sacramento. He made numerous telescopes there, the first being a 5-inch reflector.

He left the monastery in 1967, hitchhiked back to San Francisco, and co-founded the SFSA the next year with two of his students, Bruce Sams and Jeff Roloff. In lieu of formal membership meetings, club members would set up telescopes on the city sidewalk for passersby to view the heavens and learn more about astronomy.

Over time, original members of the group left the area and founded other astronomy clubs throughout the United States. And although the original chapter and some newer ones have kept their city designations, the group renamed itself the Sidewalk Astronomers in 1976. You can visit the organization’s website at www.sidewalkastronomers.us.

On March 8, in honor of Dobson, the Sidewalk Astronomers will dedicate this year’s International Sidewalk Astronomy Night to his memory. Amateur astronomers around the globe can join in and celebrate Dobson’s life and continue to carry the torch that he lit back in 1968.