To a Billionth of a Meter: Go Inside a Telescope Mirror Factory
Nov. 6, 2014 - Beneath the University of Arizona football stadium sits the Steward Observatory Mirror Lab. There, giant mirrors are meticulously shaped and polished, to be used in telescopes around the world that are helping unravel the mysteries of the universe. The time-consuming production process requires that each mirror's surface be polished down to a billionth of an inch.
The universe doesn't spill its secrets easily, say scientists who are making immense mirrors meant to be the engines of future astronomical discoveries.
In a look at the Steward Observatory Mirror Laboratory at the University of Arizona, in Tucson, we meet people on a quest for near perfection: making telescope mirrors with impossibly polished surfaces, smoothed down to a billionth of an inch (0.0254 nanometers).
Some of the mirrors will stretch 26 feet (7.9 meters) across, a technical tour de force necessary for observatories to peer farther into space, and thus further back in time, where they can glimpse the epoch of the oldest galaxies.
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