Photographic plate by James Keeler

The plate above was taken by Keeler on the night of November 6, 1899, less than a year before his death. The target of the four-hour exposure was the edge-on "spiral nebula" NGC 891, visible near the center of the plate as a dark streak with a central bulge. It is one among scores of photographs Keeler made of these beautiful and mysterious objects in the last two years of his short life, contributing so importantly to our understanding of the universe. (See the next exhibit item for more about this plate and Keeler's work with on nebulae.)

The photograph was made with Keeler's "double-slide plate holder," a simple camera mounted at the 36-inch Crossley reflector's newtonian focus. The camera, reproduced at left from Lick Observatory's posthumous publication of Keeler's photographs, consisted of a plate holder, mounted on an "X-Y stage" (one which could be moved in two directions at right angles to each other by means of thumbscrews in order to keep the target centered on the plate during the long exposure). Sadly, the actual camera appears to have been lost.

Lick photographic plate archive. The plate was refixed, washed, fitted with a protective cover glass, and provided a new envelope in 1939.