Officials behind the proposed Thirty Meter Telescope (TMT) are considering new locations for the $1.4bn facility, and expect to decide whether to opt for a new site early next year. The TMT is due to be built on Hawaii’s Mauna Kea mountain but, following protests from local residents, its building permit was revoked last December by the state’s Supreme Court. New locations that are being considered include Baja California in Mexico, the Canary Islands and Chile, as well as locations in India and China.

The TMT board had chosen Mauna Kea, which already hosts 13 other telescopes, as the observatory’s site in July 2009. Over the following six years, the organization received a series of necessary approvals and permits. However native Hawaiians, who regard the Mauna Kea summit as sacred – and who had previously objected to the growth in the number of telescopes there – carried out a protest at the telescope’s ground-breaking in October 2014.

Six months later, following further demonstrations, Hawaii governor David Ige announced a temporary postponement of the project. Then last December, the Hawaiian Supreme Court invalidated the TMT’s building permit, ruling that the State Board of Land and Natural Resources had not followed due process when it was approved. The court then remanded the case back to the board.

Looking for plan B

TMT managers began to consider other sites for the telescope in January. “The TMT’s board of directors decided to study other potential sites while the contested case takes its course in Hawaii,” says TMT spokesperson Scott Ishikawa. “We need a reasonable plan B, should the Hawaii option not be feasible in a timely fashion.”

Hawaii is still an option but we are very actively looking at alternatives

Fiona Harrison, Caltech

A key factor in the search for different locations is that construction of the TMT is planned to begin in April 2018 with completion in 2022. “It’s no secret that the TMT project is looking at alternatives, driven by schedule considerations; if you stretch the project out, the cost will go up,” Fiona Harrison, a physicist at the California Institute of Technology and member of the TMT International Observatory’s board of governors, told Physics World. “Hawaii is still an option but we are very actively looking at alternatives. We’ll be culling down [the list of sites] to a few options over the summer.”

Despite the uncertainty over the site, work is still continuing on the TMT. Fengchuan Liu, TMT deputy project manager, told SPIE’s Astronomical Telescopes + Instrumentation 2016 conference in Edinburgh last week that the uncertainty around the site has not delayed work on the telescope’s design and related issues. “The team is not sitting idle,” he says. “We are making progress and spending each dollar wisely.” He adds that a decision on a new site will be made “by early 2017”.

Still “first choice”

According to Ishikawa, the Hawaii site is still “first choice”, and the process to reapply for the permit is already under way. The case for Hawaii was strengthened by the addition last month of the TMT International Observatory (TIO) to the TMT organization as an applicant for the permit. Formed in May 2014, the TIO consists of the California Institute of Technology, Japan’s National Institutes of Natural Sciences, the National Astronomical Observatories of the Chinese Academy of Science, the regents of the University of California, as well as organizations from India and Canada.