If you wait long enough, the Thirty Meter Telescope (TMT) comes around as regularly as the comets astronomers like to observe. The controversial next-generation observatory proposed for Mauna Kea seemed dead after Native Hawaiian protesters stopped construction starts in 2015 and 2019, costs soared, regulatory approval was a moving target, and a major source of federal funding dried up.
But now, Governor Josh Green is supporting a plan to reduce regulatory uncertainty and community unrest by building TMT on the already disturbed site of a decommissioned telescope instead of the pristine ground originally planned. Particularly attractive is the site occupied until last year by the Caltech Submillimeter Observatory, which sits in a depression where the dome isn’t visible from below.
In a letter to TMT also signed by Hawaii Senators Brian Schatz and Mazie Hirono and Representatives Jill Tokuda and Ed Case, Governor Green agreed to promptly provide the developers with a clear and transparent regulatory path for this scenario—giving TMT the clarity it never had.
There’s good reason TMT remains enticing to many in Hawaii; astronomy is a clean economic driver that provides skilled, well-paying jobs that are desperately needed and seeds other knowledge industries. A photo of Mauna Kea taken from the International Space Station shows it to be an enormously large mountain, on which the telescopes leave the tiniest of footprints. You’d think reasonable people could find a way to share this resource.
However, passionate protesters believe Mauna Kea is sacred and are unlikely to back down, and politicians have feared crossing them. You might recall then-Lieutenant Governor Josh Green undermining Governor David Ige by showing supportive presence in the last protest camp wearing his hospital scrubs.
In 2022, the Legislature transferred management of Mauna Kea from the University of Hawaii to a new Mauna Kea Stewardship and Oversight Authority.
TMT’s problems extend beyond regulatory uncertainty and protests. The original estimated cost of $1 billion has grown to $3 billion, and the National Science Foundation (NSF) has withdrawn major funding, choosing instead to back the Giant Magellan Telescope in Chile.
Hawaii delegates are trying to secure TMT funding in the House and Senate budgets—if the government shutdown ever ends—but it’s a heavy lift with the Trump administration having been determined to slash NSF funding.
The TMT consortium of universities and science institutions from the U.S., China, India, Canada, and Japan is also in talks with Spain about a less desirable but more welcoming site in the Canary Islands.
TMT is unlikely to happen in Hawaii if elected officials are unwilling to defy unhappy protesters. It doesn’t help that the new TMT push comes as a bigger and potentially even uglier fight heats up over continued military use of lands many Hawaiians consider sacred.
The TMT saga is starting to remind me of the Falls of Clyde—the historic sailing ship recently sunk off Oahu due to lack of financial support and patience. Those who tried for years to save the ship had the noblest of intentions, but after many false starts, they could never gather enough money or community support to finish the deal.
https://www.staradvertiser.com/2025/11/09/hawaii-news/volcanic-ash/mauna-kea-telescope-back-new-show-or-just-a-rerun/