Giant Magellan Telescope The Giant Magellan Telescope (GMT) will be the world's largest telescope when it is completed in 2025. Instead of one large mirror, the GMT will have seven separate mirrors working together. This will mean its collecting area is bigger than the actual mirror surfaces.[1] It will be made of seven 8.4 m (27.6 ft) diameter mirror parts.[2] It will have the resolving power of a 24.5 m (80.4 ft) mirror. Its collecting area will be the same as a 21.4 m (70.2 ft) mirror. The telescope will have over four times the ability to gather light than existing telescopes. It will produce images up to ten times clearer than the Hubble Space Telescope.[3] It will cost $700 million.[4] Planned site The location of the telescope is the Las Campanas Observatory,[3] which is also the site of the Magellan Telescopes, some 115 km (71 mi) northeast of La Serena, Chile. This area has clear weather for most of the year.[5] The night sky in most of the surrounding Atacama Desert region is free from atmospheric pollution. With few cities nearby this is probably one of the places least affected by light pollution. The Giant Magellan Telescope (GMT) is a ground-based, extremely large telescope currently under construction at Las Campanas Observatory in Chile's Atacama Desert. With a primary mirror diameter of 25.4 meters, it is expected to be the largest Gregorian telescope ever built, observing in optical and mid-infrared wavelengths (320–25,000 nm). Commissioning of the telescope is anticipated in the early 2030s. The GMT will feature seven of the world's largest mirrors, collectively providing a light-collecting area of 368 square meters. It is expected to have a resolving power approximately 10 times greater than the Hubble Space Telescope and four times greater than the James Webb Space Telescope. However, it will not be able to observe in the same infrared frequencies as space-based telescopes. The GMT will be used to explore a wide range of astrophysical phenomena, including the search for signs of life on exoplanets and the study of the cosmic origins of chemical elements. The casting of the GMT's primary mirrors began in 2005, and construction at the site started in 2015. By 2023, all seven primary mirrors had been cast, the first of seven adaptive secondary mirrors was under construction, and the telescope mount was in the manufacturing stage. Other subsystems of the telescope were in the final stages of design. The project, with an estimated cost of USD $2 billion, is being developed by the GMTO Corporation, a consortium of research institutions from seven countries: Australia, Brazil, Chile, Israel, South Korea, Taiwan, and the United States. The telescope is located at Las Campanas Observatory, which is also home to the Magellan Telescopes. The observatory is situated approximately 115 km (71 mi) north-northeast of La Serena, and 180 km (112 mi) south of Copiapó, at an altitude of 2,516 m (8,255 ft). The site has been owned by the Carnegie Institution for Science since 1960. Las Campanas was selected as the location for the GMT due to its exceptional astronomical seeing conditions and clear weather throughout much of the year. The sparse population in the surrounding Atacama Desert, combined with favorable geographical conditions, ensures minimal atmospheric and light pollution. The Giant Magellan Telescope's Gregorian design will produce the highest possible image resolution of the universe over the widest field of view with only two light collecting surfaces, making it the most optically proficient of all extremely large telescopes in the 30-meter class. Site preparation began with the first blast to level the mountain peak on March 23, 2012. In November 2015, construction was started at the site, with a ground-breaking ceremony. In January 2018, WSP was awarded the contract to manage construction of the Giant Magellan Telescope. The casting of the first mirror, in a rotating furnace, was completed on November 3, 2005. A third segment was cast in August 2013, the fourth in September 2015, the fifth in 2017, the sixth in 2021, and the last in 2023. Polishing of the first mirror was completed in November 2012. Ingersoll Machine Tools finished constructing a manufacturing facility to manufacture the Giant Magellan Telescope mount in Rockford, Illinois, in December 2021. As of 2022, construction of the telescope mount was underway. The structure is expected to be delivered to Chile at the end of 2025. GMT-Consortium Large Earth Finder (G-CLEF) – an optical-band echelle spectrograph GMT Multi-object Astronomical and Cosmological Spectrograph (GMACS) – a visible multi-object spectrograph GMT Integral-Field Spectrograph (GMTIFS) – a near-IR IFU and AO imager GMT Near-IR Spectrograph (GMTNIRS) – a near-IR spectrograph The Many Instrument Fiber System (MANIFEST) – a facility fiber system Additionally, the Commissioning Camera (ComCam) will be used to validate the Ground Layer Adaptive Optics performance of the GMT facility Adaptive Optics System. Science drivers for the Giant Magellan Telescope include studying planets in the habitable zones of their parent stars in the search for life; the nature of dark matter, dark energy, gravity, and many other aspects of fundamental physics; the formation and evolution of the first stars and galaxies; and how black holes and galaxies co-evolve. The Giant Magellan Telescope is a part of the US Extremely Large Telescope Program (US-ELTP), as of 2018. The US-ELTP will provide US-based astronomers with U.S. National Science Foundation funded all-sky observing access to both the Giant Magellan Telescope and Thirty Meter Telescope. The program was ranked as the highest ground-based priority in the National Academy of Sciences Astro2020 Decadal Survey, which noted that the US-ELTP will provide "observational capabilities unmatched in space or the ground and open an enormous discovery space for new observations and discoveries not yet anticipated."