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The 200" Disk and the Hale Reflecting Telescope: Overview

Find books, articles, and archival materials on the 200" disk installed in the Hale Telescope at the Mount Palomar Observatory. For more information, please search our library catalog or contact our Ask a Librarian service.

The 200" Disk for the Hale Telescope

This guide provides historical, digital, and archival resources on the pouring of the 200" disk which was used in the Hale Telescope at Palomar Mountain in California.  When the disk was cast, it was the largest single piece of glass ever made. 

The mirror was made using Corning Glass Works' signature Pyrex®, a special glass designed to resist heat expansion. After many years of trial and error experimentation, as well as the advent of World War II, the disk was finally installed in 1948 in the Palomar Observatory. 

This LibGuide is a selective list of resources on the topic. For more information, please search our library catalog or contact a reference librarian through our Ask a Librarian service.

Find Answers to Your Glass Questions

The Pouring of the 200" disk

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