Read our COVID-19 research and news.

Artist's impression of the Thirty Meter Telescope

TMT International Observatory

Hawaii Supreme Court rules in favor of giant telescope

The Supreme Court of the State of Hawaii has cleared the way for astronomers to build one of the world’s largest telescopes atop the Mauna Kea volcano. In a 4-1 ruling, the justices rejected an effort by groups representing native Hawaiians to block a 2017 decision by state regulators to issue a permit to build the Thirty Meter Telescope (TMT). But telescope backers will still need to decide whether to move forward with the project, which is expected to cost more than $1 billion.

The ruling caps years of controversy and legal wrangling over the TMT. Some native Hawaiian groups objected to the project, saying it would mar a mountaintop they consider sacred. In 2015, protestors blocked roads to the site, preventing the start of construction. Legal action by opponents then forced state officials to reconsider a key permit for the project, but last year the telescope’s backers, which include the University of Hawaii (UH), again secured permission to move ahead. Today’s 73-page ruling upholds that decision.

“We are excited to move forward in Hawaii and will continue to respect and follow state and county regulations, as we determine our next steps,” Henry Yang, chair of the TMT International Observatory Board of Governors, said in a statement.

The decision is “disheartening,” Kealoha Pisciotta, a member of one of the plaintiff groups, Mauna Kea Anaina Hou, told Big Island Video News.

Hawaii Governor David Ige (D) and UH leaders praised the court’s decision. “We will ensure that this project is accomplished appropriately and with deepest respect for the awesomeness of Maunakea,” said UH President David Lassner in a statement

“The high court reviewed thousands of pages of documents and testimony over many years, so it’s difficult to imagine the monumental task the justices had in reaching this decision,” Ige added. “We believe this decision is fair and right and will continue to keep Hawaii at the forefront of astronomy.”

The TMT organization’s statement did not say when construction might resume and it noted there are still number of regulatory steps to complete. Prior to today’s decision, TMT officials had considered moving the project to Spain's Canary Islands.