George P. Mitchell Commits $25 Million to Giant Magellan Telescope
George P. Mitchell, founder of Mitchell Energy & Development Corp. and The Cynthia and George Mitchell Foundation, recently committed an unprecedented $25-million gift to the Giant Magellan Telescope (GMT) project. Mr. Mitchell announced his gift at a fundraising dinner he hosted for Texas A&M University and The University of Texas at Austin on May 10, 2011.
Half of the gift ($12.5 million) was made to Texas A&M University (Mitchell’s alma mater) and half to the Carnegie Institution for Science. Texas A&M and Carnegie are two of the GMT’s 10 partners. The gift will help support the GMT during the next five years.
“This is an extraordinary time for astronomy given the many mysteries, including dark energy and dark matter, that we do not understand,” remarked Carnegie president Richard Meserve. “George Mitchell’s exceptional generosity will help us to solve them.”
“This gift not only brings the dream of the Giant Magellan Telescope much closer to becoming reality, but also helps propel Texas A&M and the entire state of Texas to the forefront in the important fields of physics and astronomy,” said Texas A&M president R. Bowen Loftin.
“George Mitchell has been a driving force behind this project from the beginning,” commented Wendy Freedman, chair of the board of directors for the Giant Magellan Telescope Organization (GMTO) and director of the Carnegie Observatories. “His generosity, vision, and dedication to the project will help define the future of astronomy.”
Thus far, $255.5 million has been raised to support the GMT’s $700-million project cost.
Texas A&M: An Up and Coming Astrophysics Powerhouse
Texas A&M University is a founding member of the Giant Magellan Telescope project and brings unique assets to the collaboration. Research at Texas A&M is well-aligned with the directives of the recent Astro2010 Decadal Survey by the National Academy of Sciences which ranked the most important astronomical programs for the next decade.
Texas A&M astronomers are all working in the highest priority fields of science as recommended by Astro2010, namely the first galaxies and galaxy evolution (Casey Papovich and Kim-Vy Tran), and cosmology, the cosmic distance scale, and dark energy (Darren DePoy, Lucas Macri, Nick Suntzeff, Lifan Wang, and Kevin Krisciunas). The GMT Project is delighted to be a part of A&M’s plan for growing a vibrant astrophysics program.
Although a newcomer to the international astronomy community, the young group at Texas A&M is already establishing itself as a vital team of astronomers focused on strong research, innovative teaching, and state-of-the-art instrumentation construction. Through enthusiastic support from Texas A&M University, the University of Texas/Austin, McDonald Observatory, and the state of Texas, the astronomy program has exploded since 2006 and currently has eight research faculty and staff as well as a growing instrumentation lab and graduate program. Texas A&M astronomers are involved in several major international collaborations including the Dark Energy Survey (DES), the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), the Large Synoptic Survey Telescope (LSST), and Astronomy at the Antarctic Plateau.
Texas A&M is also home to the Munnerlyn Astronomical Laboratory where the instrumentation group (Darren DePoy, Jennifer Marshall) is already building major instruments for telescopes such as the Hobby-Eberly Telescope (HET). A primary contribution from Texas A&M to the GMT is the GMT Wide-Field Optical Spectrograph (GMACS), a proposed imaging spectrograph that covers more than a third of a degree on the sky — the largest field of view of any of the proposed instruments for any of the giant, segmented mirror telescopes! If selected as a first-light instrument, GMACS will provide simultaneous spectroscopic coverage from 3500 to 10,000 Angstroms for many thousands of galaxies at once. It will become one of the primary workhorse instruments for the GMT.
To further define the science case for the GMT, Texas A&M hosted a three-day workshop in March 2011 devoted to Extragalactic Science that included contributions from all GMT partners. The successful meeting covered a range of topics from the first stars to the nearest galaxies as well as overviews of proposed instruments. There was ample time for social interactions, including a trip to Cooks Branch, a nature conservancy managed by the Mitchell family who are generous supporters of the GMT and astronomy in Texas. With strong support within Texas as well as from the astronomy community, Texas A&M astronomy will continue to flourish and play a vital role in the GMT.
GMT Goes to Washington
GMTO recently hosted an event to educate the congressional delegations of its U.S. partners about the GMT Project. This informative luncheon, held in Washington, D.C. at the Rayburn House Office Building on June 21, 2011, was a wonderful opportunity for members of the U.S. House of Representatives, the Senate and their staffs to learn about the international partners’ efforts to create a next generation astronomical telescope that will provide a powerful new window on the universe.
Among the international dignitaries attending the luncheon were Ambassador of the Republic of Korea, H.E. Duk-soo Han, Australia’s Ambassador to the U.S., H.E. Kim Beazley, and Deputy Chief of Mission, Chilean Embassy to the U.S., Roberto Matus.
Dr. Wendy Freedman (GMTO Board Chair and Director of the Carnegie Observatories) provided the luncheon welcome and introductions. She described the GMT partners, the scientific promise of the GMT and the importance of the broadly based process for setting priorities with the astronomical community.Dr. Edward “Rocky” Kolb (Professor of Astronomy and Astrophysics at The University of Chicago and GMTO Board Member) gave an enlightening presentation entitled “Exploring Cosmic Dawn and Discovering New Worlds with the Giant Magellan Telescope” to the more than 60 event attendees. Dr. David Lambert (Director of the McDonald Observatory at the University of Texas and GMTO Board Member) provided closing remarks stressing the impact that GMT will have in education and in motivating young people to pursue careers in science and engineering. Dr. Lambert also thanked the offices of Representative Adam Schiff (CA 29th District) for arranging for the use of the meeting room in the Rayburn Building.
Representative Rush Holt (NJ 12th District) made impromptu and impassioned remarks in support of basic research and the physical sciences in particular. With advanced degrees in physics from New York University, Representative Holt’s comments carried a special weight with the event guests.
All who attended the luncheon left with an appreciation of the GMT’s importance for the future of astronomy and pride in knowing that GMT U.S. partner universities and institutions are among their constituents.
Michael Sheehan Joins GMT as Telescope Lead
Michael Sheehan joined GMT as Telescope Lead in March. Mike comes to us from Gemini, where he was Deputy Chief Engineer for operations at Mauna Kea. The telescope team has accountability for “everything above the pier” (the stable platform upon which the telescope rests). This includes the telescope structure, the optics, and the optomechanical systems that deliver light to the instruments and adaptive optics systems.
Mike is pulling together a diversified team of engineers with specialized skills in structural, optomechanical, and controls engineering to work on various pieces of the telescope system. This will all come together in an optimized design for the telescope as input for the system preliminary design review.
After completing his engineering degree at Notre Dame, Mike spent several years working in stress analysis for the state of Massachusetts. Feeling that something was missing, Mike returned to school at Tufts University where he met an important mentor: Professor Kentaro Tsutsumi. “Thanks to Professor Tsutsumi, I latched onto a whole new outlook on what an engineering life could be,” Mike says. Sheehan’s interest shifted to structural dynamics under Tsutsumi’s tutelage. “It really made engineering interesting,” explains Sheehan. “To do the dynamics is, in my mind, so much more interesting than dealing with structures that just sit still.” Large Telescopes present a unique combination of precision and dynamics that appeal to Mike’s love of a challenge.
Mike’s engineering career blossomed from that training at Tufts, first into aerospace and finally into telescopes. Almost 20 years of experience working on Gemini’s two forefront 8.1-meter telescopes (one located on Mauna Kea in Hawaii and the other on Cerro Pachon in Chile) has provided Mike with an impressive breadth of knowledge. While at Gemini North Mike contributed to the structural engineering development of the telescope and enclosure, taking these from preliminary design through completion as technical rep. As site engineer, Mike oversaw the bolt-by-bolt installation of the telescope and enclosure atop Mauna Kea. In a new role as mechanical systems manager, Mike and his family moved to Chile to work with a team to build the second Gemini Telescope from the ground up. He finished his career at Gemini as deputy chief engineer of operations at Mauna Kea.
When asked what drew him to GMT, Sheehan says, “I wasn’t thinking of moving from Hawaii, but this job was something that, as soon as I saw it, reminded me so much of those Gemini days of developing this brand new telescope, and how much I really enjoyed that time. I thought I had to explore the opportunity. I saw the job information on the GMTO website and I sent my wife a message saying I was thinking of contacting the project office. She emailed back in two seconds, saying ‘You’re nuts if you don’t at least talk to them about this opportunity!’ I’m so glad that I did,” Mike says.
Sheehan finds his work as GMT Telescope Lead to be “very exciting, because it’s all brand new. To think of the magnitude of what we’re achieving in terms of image quality with such large, movable structures, the challenges are tremendous and the rewards are incredible” he says. Mike looks forward to his telescope team continuing to grow. GMTO is actively recruiting to fill several key positions within the team, including controls engineer, two optomechanical engineers, and a mechanical designer.
When asked about his experience working with the GMT team, Sheehan says, “The people in the project are exceptional at being able to converse at a high level about the challenges we are facing. The teamwork I’ve seen around here is remarkable. The group we have pulls from individuals who are tops in their fields. It’s truly an exciting place to work. Telescopes bring you so far around the world. I’ve worked with people from Australia, Asia, Europe—from all over the planet. Astronomy has a wonderful, global, community that you don’t find in a lot of other careers.”
Giant Magellan Telescope: Recent Design Highlights
We sat down with GMT’s Telescope Design Lead, Michael Sheehan to get a firsthand update on recent telescope design highlights from the GMT Project. Mike tells us that the latest environmental test results from Las Campanas Observatory in Chile confirm that the ambient wind velocity over the site is fairly strong. The telescope must deliver stable images when operating at the relatively high wind speeds expected during science operations.
The enclosure will protect the telescope from winds to some extent, but not completely. The telescope itself must be rigid enough to keep the optics aligned to high precision. Ongoing sub-scale wind tunnel testing of the site and structures as well as future air flow modeling of the enclosure and telescope will ultimately define the design wind loads for the telescope structure.
Analyses of telescope vibration due to wind excitation are being used to optimize the geometry, materials and stiffness properties of various parts of the telescope structure. The materials of interest are basic steel and highly custom carbon fiber composites of the type used in modern aircraft. Composites are being evaluated because of their superior stiffness to weight ratio and inherent damping relative to steel. For each configuration, the telescope is subjected to the maximum operational wind loading, and image motion at the focal plane is calculated. These analyses will allow Mike to identify configurations that produce the best images during an observation. A cost-benefit analysis will feed into the decision making process leading to the final design configuration.
Chile has a very active earthquake environment as demonstrated by both recent and historic seismic events. To design the telescope properly for this environment, GMT commissioned a site specific seismic hazard analysis to define the earthquake design loads for the GMT site at Las Campanas Observatory. Criteria for the design of the telescope structure consists of two earthquake event scenarios; a moderate earthquake where the telescope must be back into operation essentially immediately after the event, and a maximum likely earthquake where the telescope can sustain damage, but not collapse or endanger people on the summit. Ongoing analyses of the telescope structure are being performed to verify that the telescope design meets these criteria
A major redesign of the Gregorian Instrument Rotator (GIR) was completed and presented to the Instrument teams in late March. In this design, the GIR can accommodate 4 large instruments in a cassette type of arrangement. The instruments are stored in a ready state on the GIR when not in use and will be commanded to move to the science position when active. The new GIR structure consists of a 9 meter diameter by 6.5 meter tall steel framework. For ease of handling and interfacing with the GIR structure, each instrument is mounted to a standard steel Instrument Mounting Frame. Mechanisms guide and drive each Instrument Mounting Frame from its stored position at the outer radius of the GIR to the central station aligned with the optical axis of the telescope. Movable counterweights are used to maintain the balance of the GIR about its axis when instruments are moved into or out of the central station.
Progress on the preliminary designs for the primary mirror segment support system components continues. We are entering a phase where prototype mirror support actuators, mirror-position-defining hardpoints and static support isolators will be fabricated and tested to ensure that they meet their performance requirements. This prototyping phase is intended to validate the design of these components prior to production of the many thousands of components needed to support the seven primary mirror segments.
A GMT Exoplanet Workshop will be held at Phillips Auditorium at the Harvard-Smithsonian Center for Astrophysics on October 17th and 18th, 2011. Further information will be posted on the GMTO website as it becomes available. For program, registration and accommodations, please visit the workshop’s info pages.
The GMT Project is looking for highly-motivated and qualified individuals to work on this world-class facility. Find out about current open positions.