48, These two 14 ½ foot diameter worm & wheel gears are used to rotate the telescope about the polar axis. One gear is used for slewing the telescope into position and the other gear is only used for drive when images are being captured. This keeps the ware down on the gear that needs to retain its precision. - photorick
The 200” Hale telescope is the forth in a series of large telescopes that George Hale envisioned and was the driving force that made those projects successful. He built the largest telescope in the world four times in a row! At the start of this project in 1938 there were several major inventions required to even make a telescope of this size possible. There are several books that chronicle the fascinating story of the construction of this telescope that are worth reading. This is a selection of photos from two visits to Palomar in the early 90’s. On the second visit I was privileged to spend three nights with astronomers as they worked on two projects related to proper motion of stars and a quasar hunt.