The Steward Obervatory Mirror Lab

Steward Observatory Mirror Lab Web Page

At the University of Arizona's Steward Observatory Mirror Laboratory, a team of scientists and engineers is making giant, lightweight mirrors of unprecedented power for a new generation of optical and infrared telescopes.

These mirrors are a radical departure from the conventional solid-glass mirrors used in the past. They are honeycombed on the inside; made out of borosilicate glass that is melted, molded and spun into shape in a specially designed rotating oven. These honeycomb mirrors offer the advantages of their solid counterparts -- rigidity and stability -- but they can be made significantly larger and dramatically lighter.

The Mirror Lab team has also developed a revolutionary new method to polish the honeycomb mirrors with a deeply curved, parabolic surface that gives them a focal length much shorter than conventional mirrors. Such so-called fast mirrors not only improve telescope performance, but they can fit into a much shorter telescope body that requires a smaller, less expensive enclosure.