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Asaph Hall

Asaph Hall (1829-1907) discovered the two moons of Mars in 1877. He was an astronomer at the Naval Observatory, 1862-1891, and was commissioned a Professor of Mathematics, USN in 1863. He was an avid double star observer, and participated in many expeditions to observe solar eclipses and the transits of Venus. Painting by Beverly Stautz
USNO Master Clock Time
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