1945 - Present

In 1945, the Loomis Telescope was reversed, with the 15-inch objective at the top, the plate holder at the foot of the tube. The telescope was thus rigidly mounted for photographing the polar region only, for the purpose of investigating the wobbling of the axis of rotation of the earth and redetermining the constants of precession and nutation.

The Loomis Telescope was moved to Bethany, CT in 1957, to continue monitoring the apparent motion of the axis of the earth. Carol Williams analyzed plates for her Ph.D. thesis, 1967. She found apparent motions largely correlated with tidal disturbances of the earth's crust.

In 1925, Schlesinger, who has been described as "the father of modern astrometry" in part for his role in perfecting the photographic methods of parallax determination, established a Southern Station at Johannesburg, South Africa. A 26-inch long-focus refractor was erected at this site for the determination of parallaxes of southern stars (it was the largest refractor in the southern hemisphere when first installed). Nearly 70000 plates were taken with this telescope, which was moved to Mt. Stromlo in 1952. The telescope was destroyed by a firestorm on January 18, 2003 which also destroyed all the telescopes at the Observatory, the library and many of the buildings as well as 500 houses in Canberra. The firestorm was a sad end to a telescope that played a major role in defining our knowledge of the distances, motions and masses of the brighter stars during the 20th century. An abridged version of this manuscript appears in the journal Astronomy and Geophysics (October 2003).

The 26-inch at Mason Lab, Yale, in 1924.

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