On cathedrals and the heavens.

…the mirror assembly and its enclosure will be 22 stories tall—the height of Notre Dame’s towers—comprising 1,163 tons of steel and glass and electronics, all moving without perceptible vibration on an oil bearing as the apparatus follows astronomers’ targets across the Chilean night sky.

via Harvard and world astronomers building Giant Magellan Telescope | Harvard Magazine May-Jun 2013.