Visible Light
Light, Sound and Waves

The mirror maestro

Stories from Physics for 11-14 14-16 IOP RESOURCES

A significant figure in the development of the telescope was the optician Bernhard Schmidt, born in Estonia in 1879. He began experimenting at a very early age and his first attempts to make lenses involved grinding together the ends of bottles he had found on the beach with sand. Aged 15, Schmidt lost his right hand in an accident with a homemade pipe-bomb but, undeterred, continued to hone his skills in grinding lenses and making mirrors.

Schmidt set up a workshop in an abandoned bowling alley and would spend days working, neglecting to eat, smoking cigars and drinking corn liquor. In the early years of the 20th century, Schmidt’s business grew and famous astronomers, including Karl Schwarzschild, sought out his products. He tested his mirrors by creating artificial stars, silvered glass balls which he hung in trees in a park and illuminated with a searchlight.

When his mirror business collapsed in the difficult economic climate after the First World War, Schmidt went on an expedition to the Philippines to photograph an eclipse. On the sea journey, he had the idea for a revolutionary new telescope, now known as the Schmidt camera, that uses a corrector plate to remedy the aberration of spherical mirrors. When Schmidt tested his prototype by observing a distant graveyard, he found that he was able to read the names on the tombstones. Schmidt cameras have wide fields of views and the Kepler Space Telescope, launched in 2009, contains a Schmidt camera which is used to hunt for exoplanets.

Accounts of Schmidt’s death vary. Official records report that he died of pneumonia, but the director of the Hamburg Observatory where Schmidt was working provided a more detailed description of the events leading to the lens maker’s death. After several days of drinking, Schmidt arrived at the observatory and began to insult colleagues resulting in a fight in which his clothes were torn. He was detained in an asylum, forced to take cold baths (a common treatment for mental health issues at the time), wear a straitjacket and died with little recognition of his contribution to astronomy.

References

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