tuscon ariz on january 14 2012 the second 84-meter (276 ft) diameter mirror for the giant magellan telescope (gmt) of which texas a&m university is a founding member will be cast inside a rotating furnace at the university of arizonas steward observatory mirror lab (soml) underneath the campus football stadium the mirror lab will host a special event to highlight the milestone of creating the optics for the giant magellan telescope and to celebrate another major step in the construction of the next-generation project as part of the festivities lab officials invite members of the media to visit their facilities on saturday (jan 14) between 9 and 11 am (mst) to see the liquid glass as it is spun cast in a rotating oven at a temperature of 1170 degrees c (2140 degrees f) there will be opportunities to interview leading scientists (including texas a&m astronomer dr darren l depoy a world-renowned expert in astronomical instrumentation and holder of the rachal-mitchell-heep endowed professorship in physics in the texas a&m department of physics and astronomy) and engineers involved in the project this event is supported by the university of arizonas steward observatory and college of science and by the gmto corporation (gmtc) a nonprofit entity with project offices based in pasadena calif project officials note the gmt features an innovative design using seven mirrors each 84 meters in diameter arranged in a floral pattern to form a single mirror 245 meters (80 feet) in diameter it will bring starlight to a common focus via a set of adaptive secondary mirrors configured in a similar seven-fold pattern in this design the outer six mirrors are off-axis paraboloids and represent the greatest optics challenge ever undertaken in astronomical optics by a large factor said roger angel director of the steward observatory mirror lab the gmt will allow astronomers to answer some of the most pressing questions about the cosmos including the detection imaging and characterization of planets orbiting other stars; the nature of dark matter and dark energy; the physics of black holes; and how stars and galaxies evolved during the earliest phases of the universe patrick mccarthy gmt project director and staff astronomer with the carnegie observatories remarked this second gmt casting is going forward now because the primary optics are on the critical path for the project and because the polishing of the first off-axis 84-meter gmt mirror is very close to completion with an optical surface accuracy within about 25 nanometers or about one-thousandth the thickness of a human hair like other mirrors produced by the mirror lab the gmt mirrors are designed to be spun cast thereby achieving the basic front surface in the shape of a paraboloid a paraboloid is the shape taken on by water in a bucket when the bucket is spun around its axis; the water rises up the walls of the bucket while a depression forms in the center precision grinding and polishing of the surface is then undertaken to create the figure of an off-axis paraboloid the novel technology developed at the mirror lab is creating a whole new generation of large telescopes with unsurpassed image sharpness and light collecting power said wendy freedman director of the carnegie observatories and chair of the gmto board the mirrors in the twin magellan telescopes at our las campanas observatory site are performing superbly and led to our adoption of this technology for the gmt some 21 tons of borosilicate glass made by the ohara corporation flow into a pre-assembled mold to create a lightweight honeycomb glass structure that is very stiff and quickly adjusts to changes in nighttime air temperature each resulting in sharper images the mirror lab has already produced the worlds four largest astronomical mirrors each 84 meters in diameter two are in operation in the large binocular telescope (lbt) currently the largest telescope in the world one is for the large synoptic survey telescope (lsst) and the fourth is the first off-axis mirror for gmt the mirror lab has also produced five 65-meter mirrors two of which are in the twin magellan telescopes at las campanas observatory in chile astronomical discovery has always been paced by the power of available telescopes and imaging technology the gmt allows another major step forward in both sensitivity and image sharpness said peter strittmatter director of steward observatory in fact the gmt will be able to acquire images 10 times sharper than the hubble space telescope and will provide a powerful complement not only to nasas 65-meter james webb space telescope (jwst) but also to the atacama large millimeter array (alma) and the large synoptic survey telescope (lsst) both located in the southern hemisphere the gmt is set to begin science operations in 2020 at carnegies las campanas observatory exploiting the clear dark skies of the atacama desert in northern chile to learn more about texas a&m astronomy visit http://astronomytamuedu # # # # # # # # # # about the giant magellan telescope: the giant magellan telescope organization (gmto) manages the gmt project on behalf of its international partners namely: astronomy australia ltd the australian national university the carnegie institution for science harvard university the korea astronomy and space science institute the smithsonian institution texas a&m university the university of arizona the university of chicago and the university of texas at austin for more information visit wwwgmtoorg click here to read a nice recap feature from the university of arizonas office of university communications -atm- contact: tina mcdowell (202) 939-1120 or tmcdowell@ciwedu or shana k hutchins (979) 862-1237 or shutchins@sciencetamuedu the post second giant magellan telescope mirror casting set for saturday appeared first on texas a&m college of science