The New Giant Telescopes

Extending the Techniques for Making Lightweight Monoiithic Mirror Bianks 

Sizes up to about 8 m are considered feasible, although the Russian 6 mis the largest telescope mirror produced before 1985. Further discussion on blank fabrication methods is provided in Section III. Supporting such large mirrors to form good images will be difficult without some active control of the surface figure and thermal conditions in the mirror blank. 

Several American universities and the national observatories in the United States and Japan are planning telescopes of this variety. 

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