Naval Research Laboratory Table Mountain, California
The mirror is a 56 × 38 cm ellipse constructed of a lightweight honeycomb core aluminum panel and mounted at a 45° angle to the axis of rotation. The mirror is rotated by an Empire Magnetics U42 stainless steel waterproof stepping motor, which is required to hold the mirror stationary to within 0.1° in 110 km/h wind. This motor has been designed to survive in the harshest of weather conditions including being buried in snow and ice at Table Mountain.
Dome A, Antarctica
Motor control of the telescope is provided by a low-temperature NEMA-34 sized stepper motor from Empire Magnetics,
A cut-away cross section of the telescope assembly is shown in Figure 4a, and a photo of the installed telescope at the summit of Dome A, Antarctica is shown in Figure 4b.
Binocular Telescope University of Arizona
US Naval Observatory, Mona Kea
Motors that could service observatories were needed.