The man who showed the heavens

John Dobson, a man who opened up the heavens for many people, passed away on Jan. 15 in Burbank, Calif. He was 98. Dobson was the inventor of the “Dobsonian” telescope design, which helped make amateur telescopes an affordable and practical proposition. His name has rock star status in amateur astronomy circles. If you ever decide to buy a telescope, be it on Saipan or anywhere else, a Dobsonian design might be in your future.

Dobson, who was born in China, earned a master’s degree in chemistry from UC Berkeley, and after a brief foray in corporate life he become a monk. While in the monastery he kept working on telescope designs, and his focus on the matter eventually resulted in him being booted from the monastery.

Dobson then became a powerful promoter of amateur astronomy, using his telescope design and his enthusiasm to open up the skies for the masses, or at least that portion of the masses willing to turn off the television set for a while. As far as I know he didn’t seek to profit from the Dobsonian design, and it was taken up by a number of telescope manufacturers. The design is also used by many resourceful folks who build their own telescopes.

In 1968 Dobson was a founder of the San Francisco Sidewalk Astronomers, an outreach organization that spawned like-minded groups all over the world.

I am one of many grateful people who were, directly or otherwise, pulled into the world of amateur astronomy thanks to John Dobson’s efforts.

Although I took several astronomy courses in high school and college, it hadn’t occurred to me to buy a telescope. I just assumed that any capable telescope would be too expensive.

A few years ago, while taking a trip, I happened upon a gathering of sidewalk astronomers. One showed me the Orion nebula through his Dobsonian telescope. The view was impressive. As it turns out, the scopes didn’t cost nearly as much as I thought they would, so I finally realized that my book learning could be hitched to doing real, hands-on astronomical observing.

So, just what is a Dobsonian design? In this high-tech age we think that revolutionary designs must be complicated, but this case is just the opposite: It’s the simplicity of Dobson’s idea that makes it so good. It’s basically a wooden box structure that cradles the bottom of the telescope, and allows the user to point the telescope around, much like a pirate pointing a cannon. It is simple, it is cheap, and it is easy to use.

It’s certainly not the best design for every need, but for many of us it’s the best design for our needs.

Anyway, since we’re talking a bit of history here, I’ll mention another name: Isaac Newton. Among his many accomplishments, Newton (1643-1727) is credited with using mirrors to do the job of telescope lenses. As old as that design is, it’s still very much with us today. Since mirrors reflect light, these designs are known as “reflectors.” Logically enough, they’re also known as “Newtonian” designs.

At this point we can connect the dots to draw the whole picture: A Dobsonian telescope is simply a Newtonian telescope (imagine the tube that is a cannon’s barrel) that’s mounted in Dobson’s design of box (imagine the wooden base that a cannon barrel sits in).

This design scales well, both going up and going down. I’ve used teeny little Dobsonian scopes that will fit into a suitcase, and I’ve used giant Dobsonians that require climbing up a ladder in order to reach the eyepiece.

Amateur telescopes can be so capable that they’re downright spooky. Even a moderate-sized scope can see many hundreds of galaxies. True, most are just faint blobs in the eyepiece. But it’s still cool.

For the sake of perspective, I’ll mention that just 100 years ago nobody apparently knew that there were any other galaxies. Although other galaxies were certainly visible, nobody really knew what they were or how far away they were. Conventional wisdom was that our galaxy is the only one. The basic scale of things was only reckoned a matter of decades ago.

We now know that the universe has hundreds of billions of galaxies, many of which (such as ours) have hundreds of billions of stars. Some have as many as 1 trillion stars.

Meanwhile, some recent estimates hold that every star out there has, on average, one planet in orbit. Sure, that’s a rough guess in a wide range, and such planets are not visible with amateur equipment, but it’s food for thought anyway.

So it’s sure an exciting time to ponder the vast and great universe above. Thanks largely to Dobson’s efforts, being able to get a good look at it is not a rich man’s game. The real price of admission to the night sky is some healthy curiosity, though it doesn’t hurt to have a taste for strong coffee.