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Giant Magellan Telescope Exploring with New Eyes The Giant Magellan Telescope (GMT) Project is an international effort to build and operate an innovative 25-meter telescope in Chile that will provide a new window on the universe. When completed, the GMT will be one of the world’s largest telescopes, with the capability to produce images with unprecedented angular resolution and sensitivity. Key Attributes Science Goals • Seven segmented primary • Origin and evolution of planetary systems and secondary mirrors • Understanding star formation • Aplanatic Gregorian optical configuration • Evolution of the chemical elements • f/0.7 primary mirror, f/8 final focus • Black hole growth • Adaptive Optics integral to telescope • Dark matter and dark energy • 368 m2 collecting area • Formation and evolution of galaxies • 10 mas angular resolution at 1 micron • First light and reionization • Sited at Las Campanas Observatory in Chile • First-light 2022 Instrument Candidates Conceptual Design studies for six candidate instruments are complete. A study for a facility robotic fiber feed is also finished. Four of these instruments are advancing through preliminary design studies. Instruments will be located at three of the five possible mount locations: the direct Gregorian feed, the folded ports below the primary mirror, and on the azimuth disk. Instrument Function λ Range, μm Resolution Field of View GMTIFS NIR AO-fed IFU/Imager 0.9–2.5 4,000–10,000 10/400 arcsec2 G-CLEF Optical High Resolution Spectrometer 0.35–0.95 20,000 – 100,000 7 x 1’ fibers GMACS Optical Multi-Object Spectrometer 0.36–1.0 1,500 – 4,000, 10,000 40–80 arcmin2 GMTNIRS Near-IR AO-fed High Resolution Spectrometer 1.2–5.0 50,000 – 100,000 Single Object MANIFEST Facility Robotic Fiber Feed 0.36–1.0 — 300 arcmin2 Integrated Adaptive Optics The GMT AO system is based on an adaptive secondary mirror composed of seven 1.05 m diameter circular segments. Six sodium layer laser beacons will enable diffraction-limited imaging and ground-layer AO correction with high sky coverage. Adaptive Optics Modes Mode Description Field of View Resolution GLAO Ground Layer Adaptive Optics 7–10 arcmin 250 mas LTAO Laser Tomography Adaptive Optics 30 arcsec 10–25 mas NGSAO Natural Guide Star Adaptive Optics 10 arcsec 10–25 mas Recent Milestones Mirror Status (November 2016) • System Preliminary Design • GMT1 mirror polishing completed Review completed • GMT2 mirror front surface polishing • Cost Review Completed • GMT3 mirror rear surface processing • Start of Construction Phase • GMT4 mirror blank cast • Groundbreaking Ceremony and cleaned out • Pre-construction site • GMT5/6/7 mirror materials infrastructure completed being procured GIANT MAGELLAN TELESCOPE A New Window on the Universe The partners in the Giant Magellan Telescope Project include 11 of the world’s leading astronomical institutions. Together, the GMT partners have hundreds of years experience in building and operating some of the world’s most advanced and productive astronomical observatories. The partners collaborate together through the Giant Magellan Telescope Organization (GMTO) Corporation, a private, non-profit organization based in Pasadena, California. Astronomy Australia Ltd. Australian National University Carnegie Institution for Science FAPESP Harvard University Korea Astronomy & Space Science Institute Smithsonian Institution Texas A&M University University of Arizona University of Chicago University of Texas at Austin GMTO.org Pasadena, California, U.S. Santiago, Chile GMT Stat Sheet_113016.
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