It’s amazing to think that just 100 years ago we believed the Milky Way was our entire universe. That was until Edwin Hubble—with the aid of a giant telescope at Mount Wilson in California—discovered other galaxies outside our own and revolutionised our understanding of the universe. Now a consortium of scientific institutions from Australia, Korea, Brazil and the United States are hoping to take us even further with the new Giant Magellan Telescope (GMT) that’s currently under construction in Chile.
Named after legendary Portuguese explorer Ferdinand Magellan (whose 1519-1522 expedition to the East Indies resulted in the first circumnavigation of the Earth), the GMT is spearheading a new wave of “super telescopes” that will revolutionise our perspective and understanding of the universe. It’s hoped this new giant telescope and others like it will help us to detect life on distant planets and see as far back as the Big Bang itself. How’s that for ambition?
The GMT project is currently under construction at Las Campanas Observatory in Chile’s Atacama Desert, having broken ground in November 2015. Its 8,500-foot altitude location is one of the driest places on Earth and is miles away from the smog and light pollution of big towns and cities, ensuring perfect observational conditions for more than 300 nights a year. First steps are to level a road to the observatory location and lay the foundations for the 1,100-ton telescope, with the project scheduled for completion sometime in 2021 at a cost of just over $1 billion. That’s a lot of green.
Of course, a giant telescope needs a giant lens. For the GMT, this will comprise seven enormous high-tech mirrors, each of which takes six years to build. With six 27-foot segments surrounding a central piece, the combined optical surface will come in at around 80 feet—more than twice the size of the 34-foot Great Canary Telescope in Spain (the current largest ground-based telescope in the world)—and will be around 10 times more powerful than the Hubble Space Telescope.
This incredible lens will collect light from the furthest edges of the universe and reflect it down through a series of mirrors to be captured by imaging cameras. From there, the concentrated light will be measured to determine how far away objects are and what they are made of. The accuracy required throughout this process is staggering; the GMT’s mirrors are curved to a precise shape and polished to within a wavelength of light (about one-millionth of an inch), and hundreds of actuators controlled by advanced computers will subtly adjust their shape to counteract atmospheric turbulence.
The GMT will be closely followed by the creatively-named Thirty Meter Telescope (98 feet) in Hawaii and the European Extremely Large Telescope (129 feet), which isn’t in Europe at all, but another Atacama Desert location. Together, they’ll help us examine distant galaxies and solar systems with unprecedented reach and clarity. We may finally discover evidence of life on distant planets, how the first galaxies were formed, what happened at the Big Bang, and what the fate of our universe will be. Huge questions, but can the GMT and other giant telescope projects deliver answers? We’ll just have to wait and see.
Q: Ever seen, or wanted to visit, one of these remote observatories? Tell us about it in the comments below.