b'Carnegie Science|Summer 2019 13The completed suite of telescopes at Las Campanas is shown here. The Swope and du Pont telescopes are on the far peak (far left). Living accommodations and other support structures (at right, with red roofs) are nestled below the twin Magellans. Today, Las Campanas is run like a city with its telescopes and support structures operating year-round, and astronomers and support staff constantly coming and going in shifts. Leopoldo Infante is the director (right) who ensures that all operates smoothly. Images courtesy Carnegie Institution for Science and Milan KarolSwope and du Pont Telescopes The Giant Magellan TelescopeThe first telescope constructed at Las Campanas was the 40-inchIn the quest for observing back to the earliest moments possible, (1-meter) Swope reflector, which became operational in 1971. It wasin 2004, the Carnegie board of trustees agreed to make a risky supported by a donation from Carnegie astronomer Henriettainvestment in a novel off-axis mirror that is pivotal to the Giant Swope (19021980). Even before it was finished, the construction ofMagellan Telescope (GMT). This next-generation telescope is a second telescope had begun, designed entirely by Carnegieslated to be commissioned in 2025. It will be composed of six astronomers and engineers. The Swope telescope still makes vitaloff-axis, 27-foot mirror segments (8.4 meters) around a central contributions to Carnegies long legacy of discovery. In 2017,on-axis segment. The segments will form a single mirror surface astronomers from the Observatories and U.C.-Santa Cruz used theof 80 feet (24.5 meters) in diameter.Swope to pinpoint the light from the light from the collision of twoWhen completed, the GMTs light-gathering power will be neutron stars. They were the first humans in history to witnessfive to 10 times that of any existing instrument.This huge such a phenomenon. The 100-inch (2.5-meter) Irne du Pontcollecting area will allow more light to be collected than any Telescope was built with a $1.5-million donation from Carnegietelescope, and the resolution will be the best-ever achieved. This trustee Crawford Greenewalt and his wife, Margaretta. It waswill help answer some of the most pressing astronomical dedicated in 1976 and named after Margarettas father. questions of 21st century. How did the first galaxies form? What are dark matter and dark energy? How did matter from the Big The Twin MagellansBang congeal into what we see today? What is the fate of the But to see farther into the universe and therefore farther back inuniverse? And importantly, are we alone?time, larger light gathering capabilities are needed. So, in the earlyAlthough the telescope is still under construction, Carnegie 1990s, planning began for two 21.25-feet (6.5-meter) telescopes scientists are already playing important roles in developing its the twin Magellans. By this time costs were steep, and Carnegiescience mission. Observatories Director John Mulchaey is on the needed partners. A collaborative effort was formed that includesGMT Board of Directors, Drew Newman is on the Science Carnegie, Harvard University, MIT, University of Michigan, andAdvisory Council, and Alycia Weinberger was one of the authors University of Arizona.of last years GMT science book, which described the telescopes The first Magellan, completed in 2000, was named forpotential for discovery.Carnegie astronomer Walter Baade. The second, ready in 2002, wasSite preparation for the GMT began at Las Campanas in named for Landon Clay, a businessman and philanthropist. TheMarch 2012 with the first of 70 controlled blasts to level the twin Magellans are considered among the best natural-imaginghighest mountaintop. The GMT has eleven partners: Carnegie, telescopes in the world. They have been used to learn about theUniversity of Chicago, Harvard University, Smithsonian chemical histories of stars, the evolution of the earliest galaxies,Astrophysics Observatory, Texas A&M University, University of the large-scale structure of the universe, and much more. ThanksArizona, University of Texas at Austin, Australian National to the development of specialized instruments such as the PlanetUniversity, Astronomy Australia Limited, the Korea Astronomy Finder Spectrograph, the Magellans play an integral role inand Space Science Institute, and Arizona State University. The Carnegies efforts to find and characterize extrasolar planets. Giant Magellan Telescope Organization manages the project.In addition to the Carnegie telescopes, Las Campanas also is home to several smaller tenant telescopes. In 2012, the first of 70 controlled blasts, began to level the highest mountaintop for construction of the Giant Magellan Telescope. The aerial image shows the footprint for the telescope as of October 2018. An artists rendering of the finished facility is shown at right.Images courtesy Giant Magellan Telescope Organization'