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"Perfect" Mirrors Cast For LSST

Posted by kdawson on from the billion-pixels-of-goodness dept.

eldavojohn writes "The Large Synoptic Survey Telescope (which was partially funded by Gates & Co.) announced a world record casting for its single-piece primary and tertiary mirror blanks, cast at the University of Arizona. From the announcement: 'The Mirror Lab team opened the furnace for a close-up look at the cooled 51,900-pound mirror blank, which consists of an outer 27.5-foot diameter (8.4-meter) primary mirror and an inner 16.5-foot (5-meter) third mirror cast in one mold. It is the first time a combined primary and tertiary mirror has been produced on such a large scale.'"

4 of 114 comments (clear)

  1. No such thing as "perfect"... by QuietLagoon · · Score: 3, Insightful

    ... perfection is only a limitation of the measurement process used to find flaws.

    1. Re:No such thing as "perfect"... by QuietLagoon · · Score: 3, Insightful

      But then the question becomes: is measurement at the atom level really good enough? Or is it accepted as good enough only because we can do no better?

  2. Re:Apparently... by ffoiii · · Score: 2, Insightful

    If only we knew who invented it... Sometimes I just wish things had names that described what they were or how they worked rather than who invented it. Credit where credit is due but isn't the value of a thing in it's use rather than it's discoverer?

  3. Re:Can someone explain... by mapsjanhere · · Score: 2, Insightful

    hmm, I think you did a d^2 instead of an r^2 in your area calculations. The actual area is 55 m^2. With glass density around 2.5 g/cm^3 you get about 20 cm thickness. What's an astonishing aspect ratio, about the shape of a saucer.

    --
    I'm aging rapidly, I bought a new game and had no idea if my machine was good for it.