Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mirror Casting Event for the Giant Magellan Telescope

10.01.2012
On Jan. 14, the second 8.4-meter (27.6 ft) diameter mirror for the Giant Magellan Telescope, or GMT, will be cast inside a rotating furnace at the University of Arizona's Steward Observatory Mirror Lab underneath the campus football stadium. The mirror lab will host a special event to highlight this milestone in the creation of the optics for the Giant Magellan Telescope.

Members of the media are invited to visit the mirror lab on Jan. 14 between 9-11 a.m. MST to see the liquid glass as it is spun cast in a rotating oven at a temperature of 1170 degrees C (2140 F). This casting marks another major step in the construction of the Giant Magellan Telescope. There will be opportunities to interview leading scientists and engineers involved in the project.

The GMT features an innovative design utilizing seven mirrors, each 8.4 meters in diameter, arranged as segments of a single mirror 24.5 meters

(80 feet) in diameter, to 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, or SOML.

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.

"The GMT will allow astronomers to observe for the first time the first stars formed after the Big Bang," said Steve Finkelstein, Hubble Fellow at The University of Texas at Austin. "I cannot wait to make these observations."

"Astronomical discovery has always been paced by the power of available telescopes and imaging technology," said Peter Strittmatter, director of Steward Observatory. "The GMT allows another major step forward in both sensitivity and image sharpness. 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 NASA's 6.5-meter James Webb Space Telescope, or JWST, but also to the Atacama Large Millimeter Array, or ALMA, and the Large Synoptic Survey Telescope, or LSST, both located in the southern hemisphere."

Patrick McCarthy, GMT project director, added, "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 8.4-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 SOML, 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.

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 world's four largest astronomical mirrors, each 8.4 meters in diameter. Two are in operation in the Large Binocular Telescope, or LBT - currently the largest telescope in the world; one is for the LSST, and the fourth is the first off-axis mirror for GMT. The UA's Mirror Lab has also produced five 6.5-meter mirrors, two of which are in the twin Magellan telescopes at Las Campanas Observatory in Chile.

"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 SOML 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."

The GMT is set to begin science operations in 2020 at the Las Campanas Observatory, exploiting the clear dark skies of the Atacama Desert in northern Chile.

"With funding commitments in hand for close to half of the $700 million required to complete the project, with one mirror essentially finished and the second about to be cast, and with the planned groundbreaking at Las Campanas in February of this year, the project is on track to meet this schedule goal," said Matthew Colless, Director of the Australian Astronomical Observatory.

"The giant mirrors being spun cast for the GMT at the Steward Observatory Mirror Lab are like the sails of the great ships of exploration ca. 1500, except here the discoveries are not lands across the ocean, but rather the nature of whole new worlds and island universes, spanning all of space and time," said Joaquin Ruiz, dean of the College of Science, University of Arizona. "We are proud to participate in such an exciting international scientific project as the GMT."

The event is supported by the University of Arizona's Steward Observatory and College of Science and by the GMTO Corp., a nonprofit entity with project offices based in Pasadena, Calif. The 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.

CONTACTS:

Roger Angel, director, SOML (rangel@as.arizona.edu; 520-621-6541)

Patrick McCarthy, director, GMTO (pmccarthy@gmto.org; 626-304-0222)

Wendy Freedman, chair, Board of Directors, GMTO
(wendy@obs.carnegiescience.edu; 626-304-0204)
Peter Strittmatter, director, Steward Observatory (pstrittmatter@email.arizona.edu; 520-621-6524)

Peter Wehinger, staff astronomer and director of development, Steward Observatory (wehinger@email.arizona.edu; 520-621-7662)

Cathi Duncan, coordinator (cduncan@as.arizona.edu; 520-626-8792)

LINKS:

For more information about the GMT, see www.gmto.org.

For images, see http://www.gmto.org/forpress.html.

The University of Arizona Steward Observatory Mirror Lab:
http://mirrorlab.as.arizona.edu

Daniel Stolte | University of Arizona
Further information:
http://www.arizona.edu

More articles from Physics and Astronomy:

nachricht New quantum liquid crystals may play role in future of computers
21.04.2017 | California Institute of Technology

nachricht Light rays from a supernova bent by the curvature of space-time around a galaxy
21.04.2017 | Stockholm University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>