Thirty Meter Telescope

Astronomy's next generation observatory.


Site Information

In July 2009, the board of directors of the TMT Observatory Corporation selected Maunakea, in Hawaii, as the preferred site to build and operate TMT. However, in December 2015, the Hawaii Supreme Court ruled that the state’s permitting process was flawed, and the State Board of Land and Natural Resources was ordered to re-do the permit process. TMT is currently working to regain the required permit and start onsite construction in Hawaii. While Maunakea continues to be TMT’s preferred site, TMT has investigated alternative sites to ensure construction can begin in a timely fashion. This webpage serves as a central clearinghouse for information related to TMT in Hawaii and alternate site studies.