Thirty Meter Telescope

Welcome to the official environmental review page for a potential future NSF investment in an Extremely Large Telescope in the Northern Hemisphere, the Thirty Meter Telescope.

Use this page to stay updated on the status of the U.S. National Science Foundation's environmental review and view opportunities for public involvement.

Why is NSF considering funding a new telescope?

Artist's conception of a multiple planet system.
Artist's conception of a multiple planet system.

Credit: Gemini Observatory Artwork by Lynette Cook

The field of astronomy is entering a new era. In the next two decades, a new class of telescope — known as Extremely Large Telescopes — can be built with capabilities well beyond that of space-based telescopes.

These new telescopes will explore the signatures of life on other worlds, answering fundamental questions about humans' place in the universe: Is there other life out in the vast expanse of space? Are there other worlds with life that future generations can explore?

NSF is considering a potential future investment in the construction and operations of an Extremely Large Telescope in the Northern Hemisphere, the Thirty Meter Telescope.

How will NSF make its funding decision?

NSF understands that the possible construction of an Extremely Large Telescope on Maunakea, Hawai‘i Island, Hawaii, is a sensitive issue that requires extensive engagement and understanding of various viewpoints.

NSF will not make a funding decision until after it considers the following: 

  • Public input.
  • The environmental review of the telescope.
  • The project's technical readiness.
  • The project proponent's management capabilities.
  • The availability of federal funding.
  • The telescope's alignment with other NSF priorities.

Note: A decision by NSF not to go forward with an investment in the construction and operations of the Thirty Meter Telescope could be made at any time, including before the environmental review process has concluded.

Where is NSF in its environmental review process?

Previously, NSF has:

  • Conducted public scoping under the "National Environmental Policy Act" (July 19–September 17, 2022). See Resources for related materials.
  • Invited public comment on its draft Community Engagement Plan (July 19–September 17, 2022).

Currently, NSF is:

  • Initiating the Section 106 consultation process under the "National Historic Preservation Act."
  • Evaluating comments received during the July 19September 17 scoping comment period.

If you have questions about the process or have any questions about using the above comment forms, please contact us at

Credit: National Science Foundation
Steps required under the National Environmental Policy Act (NEPA) and Section 106 of the National Historic Preservation Act (Section 106), with additional steps to enhance public involvement during the environmental review of the Thirty Meter Telescope.


Materials from NSF's public scoping meetings:

NSF hosted a series of public scoping meetings in Hawaii from August 9–12, 2022. All meetings included a presentation followed by a public comment period inviting oral and written comments. Materials shared at those meetings can be found below:

Related links: