Massive mirror to be cast for telescope 10 times sharper than Hubble

Technicians on Saturday will fire up a furnace in Arizona to more than 2,000 degrees Fahrenheit to pour glass to fabricate a mirror 27 feet in diameter that will be part of a giant telescope with 10 times the resolution of the Hubble Space Telescope. The mirror, which will weigh about 20 tons, will take a full year to polish to within 1/20 the wavelength of light, a tolerance on the scale of about 1 in 10 billion. http://www.latimes.com/science/sciencenow/la-sci-sn-telescope-mirror-20130823,0,2605489.story Article courtesy of The Los Angeles Times/Science Now by Geoffrey Mohan