John Dobson (Sept. 14, 1915, to Jan. 15, 2014) was an American amateur astronomer who probably is best known for designing the telescope-type named after him: the Dobsonian.
This low-cost, portable Newtonion reflector telescope is perfect for beginners and amateur astronomers of all levels.
Dobson was also known for his efforts to promote awareness of astronomy through public lectures, including his performances of “sidewalk astronomy.” This led to him co-founding the amateur outreach group, the San Francisco Sidewalk Astronomers, and the inspiration for our organization’s name: Pagosa Sidewalk Astronomers.
Because of his influence, millions of people all over the world have looked through the telescopes of the Sidewalk Astronomers.
So, what is sidewalk astronomy? Well, just as it sounds, it refers to setting up a telescope in a public place for people to view the heavens through — to stimulate interest and provide light public education. Dobson often included humor as part of his spiel to entertain passers-by.
Because busy sidewalks tend to be in light-polluted areas, sidewalk astronomers often coordinate their activities at times when brighter celestial objects like planets, the moon and bright stars are visible. Even during the day, sidewalk astronomy works via the use of solar-filtered telescopes to allow people to safely view the sun.
It’s fun and instructive to explain the workings of a Dobsonian telescope to new observers.
Light enters through the big open-end of the tube, bounces off a concave primary mirror at the bottom of the tube up to a small diagonal mirror near the tube’s top, which directs the light sideways to the eyepiece. The observer points the tube manually up/down, left/right (like a canon) using the simple altazimuth base. It is a basic point-and-look device that must be nudged along by hand. Or, as Dobson would say, “This scope runs on yogurt and eggs; I eat the yogurt and eggs.”
To enjoy Dobson’s never-ending wit and unique way with words, here’s more of our favorite quotes:
“A Dobsonian telescope is just a pile of stuff.” — Reflecting his philosophy of using cheap, everyday, recycled materials to build powerful reflectors.
“It’s crazy to live in this universe without ever having seen it.” — Highlighting his core mission to bring stargazing to the general public.
“The importance of a telescope is not on how big it is, it’s not on how well made it is — it’s how many people, less fortunate than you, got to look through it.” — Emphasizing outreach over expensive equipment.
“The sky is not a part of the park, but the park is part of the sky.” — Spoken to a park ranger who questioned the presence of telescopes.
“The exterior decorator does lovely work.” — Referring the beauty of the moon’s surface.
“All of the previous revolutions were done with cannons on Dobsonian mounts.” — His response to the “Dobsonian revolution” that the Astronomical Society in Oakland wanted to award him.
“See that dark patch [on the sun]? That’s as big as the Earth, in case you have any delusions of grandeur.” — To an individual observing the sun through his telescope.
To celebrate International Observe the Moon Night on Sept. 19, the Pagosa Sidewalk Astronomers will be in Centennial Park near the grow domes with a Dobsonian telescope from 7:30 to 9:30 p.m. Stop by and view the moon or take a picture with your phone.
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