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Observing with the "Great Equatorial"

An amateur astronomer recalls his "rediscovery" of Mars's moons with the U.S. Naval Observatory's 26-inch refractor.
The telescope that Asaph Hall used to discover the two moons of Mars in 1877 was, for a decade, the largest refractor in the world. However, it had a number of shortcomings, especially in the mounting. When the U.S. Naval Observatory moved from Washington, D.C.'s "Foggy Bottom" district to its current location in 1893, the only part of the original telescope that came "uptown" was the objective. A new mounting, complete with an elevating observing floor, was installed by the Warner & Swasey...

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