Alvan Graham Clark was an American astronomer and lens manufacturer who is best known for his role in the discovery of Sirius B. In 1857, he founded the Alvan Clark & Sons company in Cambridge, Massachusetts, which specialized in the manufacture of telescopes and scientific instruments. Clark’s telescopes quickly gained a reputation for their exceptional quality and accuracy, and the company became one of the leading manufacturers of telescopes in the United States.
Some key dates in Clark’s career as a telescope manufacturer include:
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1857: Alvan Graham Clark founds the Alvan Clark & Sons company.
1862: Alvan Graham Clark and his son William discover Sirius B while observing through one of the telescopes they manufactured.
1872: The U.S. Naval Observatory orders its first Alvan Clark & Sons telescope.
1873: The company moves to its current location in nearby Greenwood, Massachusetts.
1879: The Alvan Clark & Sons company produces the largest refracting telescope in the world, which was installed at the United States Naval Observatory in Washington, D.C.
Clark’s legacy as a manufacturer of high-quality telescopes continues to this day, and many of his telescopes are still in use in observatories around the world.