McMath-Pierce repainting

A picture of the contractors at work repainting the McMath-Pierce Solar Facility at the Kitt Peak National Observatory near Tucson, Arizona. This is a major undertaking, as the telescope is surrounded by copper pipes through which a coolant is continuously circulated in order to maintain a stable internal thermal environment. Old paint therefore cannot be removed by sandblasting, or any other forceful technique, and even the new paint must be applied carefully to avoid any risk of damage. 24th June 1991.