In 1930, a Pittsburgh plumber built an aluminium observatory that helped him meet Einstein

In the autumn of 1930, Leo Scanlon, a plumber from Pittsburgh, solved a problem in his backyard that would leave a lasting mark on amateur astronomy. Scanlon was building a private observatory behind his home in the Summer Hill neighbourhood on Pittsburgh's North Side. He needed a lightweight, weather-resistant dome to protect a homemade telescope. Instead of using heavy wood or steel, he tried a material rarely used in construction at the time: sheet aluminium. The result was the Valley View Observatory, which featured what was described as the world's first all-aluminium observatory dome. Its design became a model for later astronomy facilities and helped Scanlon secure a personal meeting with Albert Einstein four years later.Solving a weight problem behind a terrace houseAccording to historical records kept in the Stellafane convention archives, Scanlon began recording daily notes about his backyard project in September 1930. Working with a friend named Bud, he drew plans for a rotating dome that did not need an internal support frame. Instead of using heavy iron supports, Scanlon joined curved sheets of aluminium with specially folded seams on the outside. This made the dome mu...