First Aluminum Observatory Dome
Ross Township, Allegheny County, Pennsylvania
Marker Inscription
On the hill just west of here, the first known astronomical observatory with an aluminum dome was erected in 1930. Designed & built by Pittsburgh amateur astronomers led by Leo J. Scanlon, the Valley View Observatory stood beside his Van Buren St. home. In the ensuing years, many of the world's observatories were built with such domes. Scanlon's shiny metal dome became a model for the popular image of a modern observatory.
Erected by Pennsylvania Historical and Museum Commission
The Story
On a hill just west of here in 1930, a band of Pittsburgh amateur astronomers led by Leo J. Scanlon raised the first known observatory dome made of aluminum, beside Scanlon's own home. Their Valley View Observatory proved that the lightweight metal — newly cheap thanks to nearby aluminum pioneers — made an ideal, weatherproof dome. In the years that followed, observatories the world over adopted the shiny metal dome that became the very image of modern astronomy.
Why it matters
A hobbyist's backyard experiment set the template for how observatories everywhere would be built, a small but vivid case of amateur ingenuity shaping science worldwide.
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Related people
- · Leo J. Scanlon
Themes & tags
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