Diorama housing the original Newtonian mirror cage from the 100-inch Mount
Wilson reflector, on loan from the Carnegie Institution of Washington.
Edwin Hubble is at the Newtonian focus. Eric Long photograph, National
Air and Space Museum.
Soon after the original Herschel 20-foot tube arrived at the National
Air and Space Museum on loan from the National Maritime Museum, staff
photographer Eric Long took a series of documentation photographs. For
this one, curators placed the original 18.5-inch speculum metal mirror
at the base of the tube, kept the access door open for illumination, and
Eric photographed what an observer would see from the top end of the tube
in "daylight," from what has become known as the Herschelian
focus. Eric Long photograph, National Air and Space Museum.
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