UT-Austin just took a big step in its process of building one of the largest telescopes in the world as the Giant Magellan Telescope is moving into its final design phase to get federal funding through the National Science Foundation.
According to Taft Armandroff, director of UT’s McDonald Observatory, discussions of the GMT started about 25 years ago among astronomers, but it’s been seriously in the works since 2014 as academic institutions (including UT-Austin and Texas A&M) and private donors started putting in money.
Currently, the GMT has fundraised about $1 billion for the project as UT-Austin and 15 other universities and research institutions are working on this project.
Armandroff told the Chronicle that current larger telescopes, like at UT’s McDonald Observatory in West Texas, can’t see far enough, and the GMT will be five times more powerful.
The telescope is being built in pieces around the country, but it will be located in the Atacama Desert in Chile. Armandroff said this is because light pollution is so low there that the skies are clear for more than 300 days a year.
Even though the private funding started 11 years ago, GMT has been working to get federal funding from the NSF, which makes grants for research-based projects, particularly in universities. According to Armandroff, the total estimated cost of the telescope and related expenses is $2.6 billion.
Armandroff said the process for getting federal funding has been long, but it’s nearing the end. Chances seem good. They’ve passed two design phases already.
“They had a review committee look at all of our drawings and concepts and plans, and these are worldwide experts in building telescopes and instruments. And they gave us a very high grade,” Armandroff said.
NSF has “chosen to move forward at this very challenging time, so we’re hoping that means we’re a priority.” – Taft Armandroff, director of UT’s McDonald Observatory
Even though the federal government continues to slash funding and government programs, Armandroff believes that GMT will likely still receive funding. However, if funding was denied, Armandroff said GMT would look for more university partners and private philanthropists.
“If the NSF didn’t plan on funding this eventually, why would they move us to the final design phase?” Armandroff said. “Wouldn’t they say, ‘Sorry, the administration isn’t interested in this or this isn’t the time for this?’ But they’ve chosen to move forward at this very challenging time, so we’re hoping that means we’re a priority.”
While GMT is waiting for funding, some of the larger and more time-consuming aspects (like the large mirrors and roads around the telescope in Chile) are already being worked on.
The Atacama Desert is over 4,000 miles from Austin, but Armandroff said UT students will have a room in Austin to study the data from the telescope and make observations.
With this large project continuing on track, Armandroff believes the U.S. will not fund another telescope of this caliber in the foreseeable future. Armandroff projects that the final design review will occur in early 2027, and then go into congressional budgets about six months later. He expects the telescope to go online in the 2030s.
This article appears in June 27 • 2025.