Sidewalk astronomy

Lore & Background

Examples of people setting up telescopes on urban streets for public astronomical viewing go back well into the 19th century and maybe even further. Sidewalk astronomers and their telescopes have been a common sight in most big cities. Historical figures include Frank Manning in New Orleans as early as 1930 and Mr Grosser in Los Angeles in the 1870s, who not only set up a telescope but also an illuminated microscope. Some sidewalk 'pitch men' charged the public to view astronomical objects through their telescope, while other astronomers allowed people to view for free. In more recent years, sidewalk astronomy has come to be more associated with altruistic individuals or groups offering views of the nighttime sky as a free public educational service.

Because 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. During the day, sidewalk astronomy often includes the use of a solar filter on the telescope to allow people to view the Sun. Telescopes used are often larger than the average available 'department store telescope', sometimes very large. With the advent and growth of organized amateur astronomical groups, sidewalk astronomy has come to be associated with public education about astronomy via free public viewing for anyone who wishes to look through the telescope. This usually involves an individual or a group of amateur astronomers with small-to-medium-sized telescopes.

Reader's Guide

Sidewalk astronomy's significance lies in its role as a direct, public-facing form of amateur astronomy that prioritizes education and accessibility. The article notes that organizations such as the San Francisco Sidewalk Astronomers, founded by John Dobson, are organized around the idea of educating people about the universe they live in by having them look through telescopes. Dobson promoted a design for a large, inexpensive reflecting telescope that he called a 'Sidewalk Telescope', more commonly referred to as the Dobsonian telescope. This design made larger telescopes more affordable and portable, further enabling sidewalk astronomy. The practice has evolved from a mix of for-profit and free offerings to a predominantly altruistic educational activity, with groups and individuals setting up in urban areas to share views of the Moon, planets, bright stars, and even the Sun (with a solar filter). Its legacy is tied to the growth of organized amateur astronomy and the democratization of telescope viewing for the general public.

Did You Know?

• Sidewalk astronomy dates back at least to the 1870s, with Mr Grosser in Los Angeles.
• Some early sidewalk astronomers, called 'pitch men', charged the public for views.
• John Dobson promoted a large, inexpensive reflecting telescope design called the 'Sidewalk Telescope' (Dobsonian).
• During the day, sidewalk astronomers often use a solar filter to allow viewing of the Sun.