Hingham, Massachusetts. Dynavac, a market leader in precision optical coating systems, engineered and manufactured the optical coating system for the Lowell Observatory’s newly commissioned flagship telescope: the Discovery Channel Telescope (DCT), the fifth largest optical telescope in the continental United States. Dynavac is one of a handful of companies in the world with the capabilities to design, engineer and manufacture the mirror deposition system for the four-meter class “super-scope” telescope. Light from the universe reflects off the DCT’s primary and secondary mirrors, and it is Dynavac’s thin film deposition and vacuum technologies that created the reflective, aluminum surfaces of the giant mirrors. Dynavac also co-sponsored the First Light Gala commissioning the telescope, and is featured in the Discovery Channel’s documentary, “Scanning the Skies: The Discovery Channel Telescope.”
“Having the ability to aluminize the DCT’s mirrors on site is a real advantage, and the Dynavac system is working very well,” says Jeffrey Hall, Director of the Lowell Observatory. “We coated the 4.3-meter primary mirror successfully on our very first try, and the excellent quality of the aluminum coating matches and preserves the excellent quality of the mirror figure. We’re very pleased with the results.”
Dynavac assembled and tested the system in its manufacturing facility in Hingham, Massachusetts, and then transported and installed it at the summit of the observatory in Arizona. The vacuum chamber is 16 feet in diameter and has an overall height of 14 feet. The DCT mirrors were supported on frames mounted in the shallow base of the chamber. The upper chamber cylinder held the evaporation sources, which were distributed in a set pattern to achieve a coating thickness uniformity of better than +/- 5% over the surface the mirror.
The Fifth Largest Telescope in the Continental U.S.
The six-ton telescope is located in the Coconino National Forest near Flagstaff, Arizona. The primary mirror alone weighs about 6,700 lb. (3,000 kg). The mirror was mounted on the telescope in August 2011, and the telescope saw first light in May 2012, including breathtaking images of M109, a barred spiral galaxy 84 million light years away.
The DCT is designed to spot fainter objects, such as asteroids and comets in our solar system, which reflect light poorly. As Hall explains, “Most people ask how far a telescope can see, but an equally important question is ‘how faint can it see?’” The telescope will also be used to probe beyond the orbit of Neptune, and help answer scientific questions like how the solar system formed and the evolution of galaxies.