The Sidewalk Astronomers

One of the problems of human knowledge is that the world which we see from the surface of this planet on a sunny day bears almost no resemblance to the rest of the universe. Our Earth is made of iron and rock; but the universe as a whole is mostly hydrogen. The actions which we see on the surface of the Earth run mostly on sunlight; but the universe runs mostly on gravity. However, the universe at large is without water and sunlight. It is for the most part a dark, lonely void lightly seasoned with hydrogen, helium and the leftover dust of exploded stars. These elements have fallen together by gravitational attraction to form galaxies, stars and planets. The blueness of our daytime sky is not the color of the air; but simply the shorter wavelengths of light scattered through the sunlit gas layer which surrounds us. And this gas layer by night, unlit by the Sun, is sufficiently transparent so that we may gaze through it, into the far reaches of the universe.

Because of this unfortunate discrepancy between what we see here by day and what we can see by night, some of us have endeavored to make it possible for other human dwellers on this planet to see the universe at large through telescopes. It is for this objective that those who call themselves the Sidewalk Astronomers have banded together. In order to increase the amount of equipment available for this effort they help and encourage others to build telescopes; and they get their own telescopes out for public use. The problem of making it possible for everyone to see and understand the universe in which they live has reached staggering proportions.

Since 1968, our primary purpose has been to fill the public need for astronomical observation. We entertain the public with large, portable telescopes on the sidewalks of the cities. We also gove star parties and astronomical slide shows in schools, museums, state and national parks and monuments; so that the viewers may understand what they see through the eyepiece. The great astronomical observatories cannot possibly handle the public appetite for celestial observation. That is the mission of the Sidewalk Astronomers; and it is why we go to such trouble and expense to transport the telescopes so far from place to place.

Unfortunately, the universe at large can no longer be properly seen from the cities. Just as the Sun's light is scattered by the atmosphere by day, the light from the cities is scattered into the atmosphere by night, making it virtually impossible to get a good view of the heavens beyond the confines of our little solar system. Here, the objects are both close and lit by the Sun but in order to see into the depths of the universe, it is necessary to get both the telescopes and the observers to the mountains; or at least far from the glow of city lights. Within the national parks there are many suitable places high above sea level and far from city lights, that are visited by millions of people each year. That is why the Sidewalk Astronomers take their telescopes there whenever they can afford to do so. By now, more than a million people have looked through them; but that is only a drop in one of many buckets. Billions of eager eyes are waiting!

Although the Sidewalk Astronomers, as a group, was founded many years ago, John Dobson, often referred to as their founder, had already been engaged for a decade earlier in making telescopes for public service. Initially, he made telescopes by grinding the mirrors from discarded ship's windows and the bottoms of gallon jugs. Most of them were twelve inchers, six or seven feet long, mounted on what are now known as "Dobsonian" mounts. They were wheeled from house to house on old rusty wheels from children's discarded wagons. He would wheel a telescope down the street till someone asked what it was. "It's a telescope," he would reply, "Do you want to borrow it?" Usually the answer would be yes, and they would look for a place where he could leave it for a month, so the people in the neighborhood could use it. Often, he would operate the telescope and explain to the viewers what they were seeing.

Inspired by this new perspective, many others have since joined the Sidewalk Astronomers in their quest to reveal the glory of the cosmos to anyone possessing enough curiosity to stop and gaze skyward with us. Together we stand, watchers of the skies, in awe of the majestic beauty of the universe.


You are invited to go along on our astronomical tours to schools, museums, state and national parks and monuments; or to meet us when we set up the telescopes on the sidewalks in town. Feel free to call us up to find out where we'll be.

San Francisco Sidewalk Astronomers
1801 Golden Gate Avenue
San Francisco, CA 94115
(415) 567-2063 or (415) 681-2565

San Francisco (North Bay) (415) 453-2885
Eureka, CA (707)786-4956
Los Angeles (818) 842-6484
Oregon (503) 838-5697
Washington State (360) 438-1637
Massachusetts (508) 896-2233
New Mexico (505) 682-3657
Fort Worth, TX (817) 421-5658
Maryland (301) 340-3938
Montana (406) 683-4081
British Columbia, Canada (250) 353-2264
* * You are welcome to join or help us! * *

A non-profit organization dedicated to public service in astronomy. Annual dues are $15.00 and include quarterly newsletter.

Sidewalk Astronomers
1946 Vedanta Place
Hollywood, CA 90068

For information on John Dobson's schedule call (818) 842-6484

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1998 The Sidewalk Astronomers