(EDITORS: News reporters and photographers can arrange access to the Mirror Lab during casting with Peter A. Wehinger at Steward Observatory, tel: 520-621-7662, fax: 520-621-7852, e-mail: pwehinger@as.arizona.edu)
TUCSON, Ariz. — If you think it’s hot at 100 degrees in Tucson today, imagine the noontime temperature at 482 degrees Fahrenheit.
That’s how hot it was at noon today inside the University of Arizona Mirror Lab furnace. UA Steward Observatory astronomer John Hill predicts that temperatures very early Saturday morning (May 20) will hit 2,100 degrees — so hot you can watch glass melt.
Actually, you CAN watch 41,140 pounds of glass melt inside the Mirror Lab furnace. Visit the Mirror Lab web site
(http://medusa.as.arizona.edu/mlab/lbtcast2.html) and click on "casting
pictures." The best views of melting glass will begin Friday afternoon, May 19, according to Mirror Lab manager Steve Miller.
The Mirror Lab’s two-story rotating furnace features special cameras so scientists — and, via the Internet, interested spectators — can watch as solid chunks of borosilicate glass soften to the consistency of Jello, then to the consistency of thick honey. The glass will flow around the cores of the mirror mold to form the honeycomb structure of a giant telescope mirror.
The UA Steward Observatory Mirror Lab is casting this glass for the second 8.4-meter-diameter (27.6-foot) mirror for the Large Binocular Telescope (LBT). The two big mirrors will be mounted side by side on a single telescope mount in the $84 million telescope under construction on Mount Graham, Ariz. Once in operation in 2004, the LBT will be the world’s most powerful single telescope for optical and infrared astronomy.
The Mirror Lab turned the furnace on at 6:30 p.m. last Saturday, May 13. "The initial heating is quite gentle to drive off any residual water in the mold," said Hill, LBT project director.
If all continues to go well, the furnace will reach 1,382 degrees F (750 degrees C) and start spinning at 7 a.m. Friday, he added.
For more on the telescope project, visit:
The Steward Observatory, http://www.as.arizona.edu
The Steward Observatory Mirror Lab, http://medusa.as.arizona.edu/mlab/
The LBT Core-Naming Campaign, http://medusa.as.arizona.edu/lbtwww/cores/
The Large Binocular Telescope, http://medusa.as.arizona.edu/lbtwww/lbt.html