Community access to the new 6.5-m telescope of the MMT Observatory will begin in March, 2000. Good progress is being made toward replacing the 4.5-m Multiple Mirror Telescope atop the 8500 foot summit of Mt. Hopkins, about 40 miles south of Tucson, Arizona. The new telescope uses a 6.5-m (256 in) spin-cast honeycomb mirror that was cast and polished in the Steward Observatory Mirror Lab. The conversion of the telescope is jointly funded by the University of Arizona and the Smithsonian Institution. The project is being directed by MMT Observatory in close cooperation with University of Arizona and Smithsonian scientists and engineers.
The new telescope will be a general purpose optical/IR telescope. All instruments will mount at the Cassegrain focus. The telescope will have three focal ratios: f/9 for feeding existing MMT instrumentation, f/5.4 giving a field of view of one degree for multi-fiber spectroscopy and 30' for optical imaging, and f/15 for infrared observations. The f/15 secondary will be adaptive with the goal of producing diffraction-limited images at wavelengths of one micron and longer. The staging of the implementation of these configurations is such that the f/9 secondary will be integrated in fall 1999 with the other two arriving sometime in 2000.
First light at f/9 Cass is anticipated in the fall of 1999. Instrument integration and high-risk scientific observations will begin shortly thereafter. All observations for at least the first half of 2000 will be made at the f/9 focus.
Craig Foltz