New stewardship of Mauna Kea, a dormant volcano that hosts some of the world’s largest telescopes, could change the face of astronomy at the summit.

Mauna Kea Observatories panorama
From left-to-right: United Kingdom Infrared Telescope, Caltech Sub-Millimeter Observatory (closed 2015), James Clerk Maxwell Telescope, Smithsonian Sub-Millimeter Array, Subaru Telescope, W.M. Keck Observatory (I & II), NASA Infrared Telescope Facility, Canada France Hawaii Telescope, and Gemini North Telescope
Frank Ravizza / CC BY-SA 4.0

The University of Hawaii has overseen the construction of 13 telescopes on the peak of Mauna Kea over the past 50 years — each one larger and more groundbreaking than the last.

But with the passage of a law inspired by Native Hawaiian protests, the volcanic summit will soon transition to new management: an 11-member board that includes a broad spectrum of voices. With the observatories’ leases up for renewal in 2033 and the construction of the Thirty Meter Telescope still in limbo, the re-organization could change the face of astronomy at the summit.  

At the Crossroads

Since the 1960s, Mauna Kea has come to symbolize a touchpoint between groundbreaking science and cultural traditions. The university built its first, 2.2-meter telescope on the summit in the 1960s, and in 1968 the Hawaiʻi Department of Land and Natural Resources gave the University of Hawaii a 65-year lease for land within a 4 km (2.5 mi) radius around it. The generous lease amounts to almost all of the summit above 11,500 ft (3,505 m).

Sean Goebel

The university has subleased land from this Maunakea Science Reserve to an increasing number of observatories over the years, including the W. M. Keck, Gemini, and Subaru observatories. The atmosphere above the mountain is dry and thin, and the skies are exceedingly dark, ideal for visible, infrared, and millimeter-wavelength observations of the universe.

The telescopes on the summit have proven invaluable to astronomy — they’ve mapped the Milky Way, confirmed the presence of the Kuiper Belt in the outer solar system, and provided hard evidence of the supermassive black hole in our galaxy’s center.

But new construction often occurred over the protest of Native Hawaiians, to whom the summit is the sacred meeting point of Papahānaumoku (Earth Mother) and Wākea (Sky Father). Protestors have also cited environmental reasons, with concerns for endangered birds and insects that make their homes in the summit’s fragile habitats. Others listed aesthetics, since the observatories affect the sightline along the summit.

TMT protest on April 2, 2015
Arrested protesters chant before police remove them from the summit of Mauna Kea on April 2, 2015.
Occupy Hawaii

In recent decades, such protests have become more powerful, resulting in the cancellation of a plan for four to six “outrigger” telescopes around the Keck Observatory. More recently, sit-ins have stymied the construction of the Thirty Meter Telescope (TMT) multiple times, in 2014, 2015, and again in 2019. (Protestors remained until March of 2020, when they disbanded due to COVID-19 concerns; construction likewise stalled due to the pandemic.)

Pushback wasn’t universal, though: Polls in 2019 showed that two-thirds of Hawaiian residents supported the TMT, as did half of Native Hawaiians. Nevertheless, mistrust and misinformation were at an all-time high. In response, the Hawaii house of representatives convened a working group, and that group in turn recommended the creation of the Mauna Kea Stewardship and Oversight Authority to oversee the summit. After a transition period of five years (starting July 1, 2023), this new group will manage all of Mauna Kea.

Now the Work Begins

Under this law, the Mauna Kea Authority will have jurisdiction over all state-leased lands on Maunakea, including the 550-acre astronomy precinct that hosts 12 of the 13 telescopes, the Halepōhaku complex that hosts visiting astronomers, and the access road that takes visitors up to the summit. The Mauna Kea Authority will also have jurisdiction over the remaining 9,450 acres of what are now designated conservation lands.

The 11-member Authority will contain one representative each from the Board of Land and Natural Resources, Hawaii County, the University of Hawaii, and the Mauna Kea Observatories. Five additional members will have experience in resource management, education, business and finance, and Native Hawaiian practices, including practices that involve Mauna Kea specifically. The Hawaiian House of Representatives may also appoint two members to the board. The Authority will take action based on majority vote.

Prospects for Renewal

The members haven’t been appointed just yet, but once they are they’ll have their work cut out for them. “There are many open issues for the Authority to address; foremost would be the nature of the new lease for the Observatory beyond 2033,” says chief scientist John O’Meara (Keck Observatory).

Lease negotiations for telescopes not already set to be decommissioned will begin in 2028, because while the leases run out in 2033, it can take years to decommission a telescope. Under previous agreements, the University of Hawaii is already planning to remove five telescopes and restore their sites — no new telescopes will be placed there.

Caltech Submillimeter Observatory
Caltech's Submillimeter Observatory, which stopped operations in 2015, is due to be decommissioned this year. The decommissioning process includes restoring the site.
University of Hawai'i

The first of these is Caltech’s Submillimeter Observatory, which closed in 2015. “It took seven years to get the permits to decommission that telescope,” says TMT executive director Robert Kirshner. “Nothing is simple!”

The next site to be restored is the Hōkū Keʻa Observatory, which holds a 36-inch teaching telescope, then the United Kingdom Infrared Telescope, the James Clerk Maxwell Observatory, and a fifth telescope yet to be determined.

The existing telescopes currently lease their land at the rate of $1/year — a holdover from attempts in the 1970s to bolster Hawai‘i’s faltering economy following a tsunami and other challenges. (The observatories do, however, contribute $4.4 million per year to mountain maintenance, which includes everything from plowing the access road to funding the study of wēkiu insects that live among the summit’s cinder cones.) Under current agreements, the Thirty Meter Telescope would pay $1 million per year in rent once built. One can imagine similar agreements being put in place for other existing telescopes.

The Thirty-Meter Elephant in the Room

Thirty Meter Telescope enclosure and site
The Thirty Meter Telescope will be set down and away from the other observatories already at the summit, as shown in this artist's illustration.
TMT International Observatory

The other issue facing the Authority — eventually — is the Thirty Meter Telescope. For now, though, the TMT's future is in the hands of the National Science Foundation, which is conducting an environmental review for the TMT. Although the observatory has passed such reviews before, this one is part of a new process by which the TMT would receive federal funding; as such, it’s not related to the state’s Mauna Kea Authority.

The TMT International Observatory has made efforts to address concerns with the new facility, which will be larger than previous ones due to the telescope’s sheer size. The University of Hawaii has made a legally binding statement ensuring that this will be “the last new area on the mountain where a telescope project will be contemplated or sought.” The building will also not be at the summit itself but 500 feet down, down a 1-mile road. “This site has excellent properties for astronomy, was not in use for cultural activities, and makes the enclosure, just a little taller than Subaru’s, much harder to see from much of Hawaii Island,” Kirshner says.

“We will work with the new authority to support astronomy and education in harmony with the culture and environment of this special site,” he adds. “We are active in building relationships with the local community.”

Size of TMT relative to existing and planned telescope
The Thirty Meter Telescope facility would be small relative to other "extremely large telescopes." The latter are planned for Southern Hemisphere sites in Chile and will see different parts of the sky than TMT.
TMT International Observatory

Much work remains to be done, O’Meara adds: “We need to make sure that the Authority has a great start, so that everyone can participate under the mutual stewardship principle. That way we can best move forward with clear eyes.”

Editorial note (Sept. 12, 2022): Corrections were made to the make-up of the Mauna Kea Authority and the land the Authority will oversee based on the approved bill.


Mauna Kea


Image of Lou


September 1, 2022 at 4:31 am

Whoa, being an astronomer in the 21st Century is becoming quite a battle: in addition to the usual problems of fighting for funding, time, and weather, now you must fight for the sky (Starlink) and even fight for land!

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September 1, 2022 at 4:44 am

In response to the caption for the family portrait shot: CFHT (Canada-France-Hawaii Telescope) next to Gemini North says "hey, what about me?" 😉

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Monica Young

September 6, 2022 at 9:06 am

Thanks, Lou, I've added CFHT to the caption 🙂

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Chris Neyman

September 9, 2022 at 7:19 pm

It’s equally true to say all the telescopes will have 10x worse resolution than Hubble!

Please provide some context for the figure comparing the resolution of existing and future large telescopes at bottom of the page “with resolution times Hubble”. As currently stated it may give the reader an inflated sense of the improvement provided by the next generation of extremely large telescopes.

Remember resolution depends on wavelength and diameter. Perhaps you intended to make the figure for a wavelength of 2.2 microns in the IR. They I would say your figure is fine, current adaptive optics systems planned for the ELT’s should reach the diffraction limit at these wavelengths resulting in resolution improvement as stated at the bottom of the figure. However, Hubble isn’t really an infrared telescope so a better comparison would JWST. Then the gains would be a more modest, 1.26, 1.25, 4.62, 3.91, and 6.05 times JWST.

If we shift to the visible (say 500 nm) the all the telescope only have a resolution of 1.0-0.5 arc seconds because they are sitting at the bottom of Earth’s atmosphere. Hence resolution ten times worse than Hubble’s 0.04 arc seconds. Now you can hope for an adaptive optics system than works in the visible but ones planned for these giant telescope are “ground layer” only they don’t achieve the diffraction limit at best they only get to about 0.2-0.1 arc seconds, so now only five times worse than Hubble. Perhaps in the future adaptive optics will provide full diffraction limited resolution across the visible spectrum, but until then nothing like the factors on your figure.
I would also like to point out that Hubble in the visible has a resolution of 0.04 with is slightly better than the current generation of telescope can achieve in the infrared (0.05-0.06 arc seconds) with adaptive optics.


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September 18, 2022 at 6:01 am

The graphic comes from, not S&T. Besides, spectral resolution (rather than imaging resolution) is where ground-based telescopes have space-based totally licked and at a fraction of the cost. If you read the recent decadal survey, future advancement/discoveries depend on pushing into the IR (early Universe, starbirth, exoplanets of red-dwarfs, Galactic Center), especially when following-up observations by Webb. Oh, but did you see Gemini South's recent image of R136a1 which used lucky-imaging to achieve 0.03 arcsecs? 🙂

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Donald W.-Bennett

September 1, 2022 at 5:32 pm

The TMT should have cut it's loses a long time ago and began construction on their alternate site. Hawaii is an unreliable partner for this project and will drag it's feet forever. The rest of the telescope operators should be seriously making plans to decommission their facilities because the writing is pretty much on the wall that there will be no telescope operating after 2033.

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Anthony Barreiro

September 1, 2022 at 6:52 pm

Thank you for this thorough and well balanced report.

I would imagine that most readers of Sky and Telescope are biased in favor of telescopes! But please try to remember that Mauna Kea was sacred land for the Hawaiian people long before telescopes were even invented.

I hope that the Mauna Kea Stewardship and Oversight Authority will be able to find solutions that respect the interests and meet the needs of native Hawaiian people, local communities, the ecosystem, and astronomy. Mauna Kea is a unique and remarkable place. Hopefully everyone can listen to one another with open hearts and minds and work together.

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September 5, 2022 at 3:51 pm

It's not usually possible to reason with superstition as the two words are an anathema to each other. A open mind and primitive dogma usually means the open mind must give in to the intransigence of the "true believer."

Sadly, over a half century after man first walked on the Moon, science is falling victim to ignorance and superstition because of a vocal minority who believe that one pile of dirt is more "sacred" than another.

It's a sad state of affairs when the majority bows and allows the screaming mob to tear down astronomical observatories...the culmination of human intellectual achievement.

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September 1, 2022 at 10:04 pm

For a lot of people these telescope buildings are eyesores just as much as all the StarLink and other satellites are for "most readers of Sky and Telescope". Ironic, no?

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September 2, 2022 at 5:21 pm

I have visited many great observatories including Lick, Palomar, Lowell, and McDonald, and I have observed at night through the Great 36" Refractor at Lick Observatory. Being inside any great observatory dome, especially at night, is every bit like being inside a sacred church. Churches and observatories are, in very different ways, reaching skyward for answers to some of life's foremost questions. The fact that there are now astronomical observatories residing on the top of Mauna Kea is a continuation of the reverence and searching that led ancient Hawaiians, and no doubt only the highly revered spiritual leaders, to trek to the summit in search of answers to their questions. Today everyone can partake of the knowledge brought down to Earth from the heavens above Mauna Kea. The native Hawaiians who oppose more construction on Mauna Kea have their opinions and concerns, and maybe the TMT should be the last telescope ever built at that location, or maybe it should not be built there at all. But who's to say if the ancient leaders who climbed that mountain, and who had their own connections with the stars from that lofty site, would not today see the observatories in a different light and have an appreciation for these astronomical temples that those who protest the observatories being on the mountain do not see.

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September 2, 2022 at 5:39 pm

TMT will never be built in Mauna Kea. This article cherry picks pro TMT issues. 2/3 of Hawaiians DO NOT support TMT. Where are these "facts" coming from? The author barely scratched the surface of WHY Kanaka Maoli don't want TMT.

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Monica Young

September 6, 2022 at 8:46 am

I linked to the poll results that showed the support and opposition to TMT; if there is a problem with that poll, I would appreciate it if you would let me know. It's true, however, that there's a lot of history here and many issues at stake that you'd really need a book to comprehensively cover.

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September 3, 2022 at 2:31 am

Perhaps the native Hawaiians could regard the telescopes as an enhancement of their sacred site, providing an even closer meeting point between Earth Mother and Sky Father?

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September 5, 2022 at 10:05 am

Be quiet, John. You are embarrassing yourself. Did your parents teach you no manners or respect for other people?

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September 5, 2022 at 4:09 pm

I am afraid it is you that has embarrassed yourself!
Respectfully, this is supposed to be a free country. You may not tell John to be quiet. You do not have the right to bully John from his right to free speech. Nor did you need to attack his parents.
John reasonably expressed his opinion on this thorny subject without personally attacking anyone. I dare say his opinion is likely shared by many. Lets try to keep comments on a friendly astronomers, we have enough challenges without stooping to social media behavior.

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September 5, 2022 at 10:08 am

Here's hoping for a peaceful solution, which will have to be a compromise of some sort if it is to respect everyone's interests and traditions. I look forward to what new telescopes may show us, but our techno-myths and techno-religion are no more important (and no less important) that aboriginal beliefs.

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September 6, 2022 at 5:47 pm

I will have to say in many ways they are, because here in Canada we are seeing many economic-enhancement projects curtailed because the land happens to now be sacred. Up until a potential project planning and build stage, no one cared. But when $$ are involved, then everyone pipes in. And many are just followers with no real opinions other than parrotted ones form the internet or their own group (followers, not reasoners). Usually these projects take as much as possible to minimize or virtually eliminate the impacts, but there are still folks wanting to stop ANYTHING involving change.

However, this particular situation is IMO a bit different. Why? Because the Hawaiian peoples have been both a sea faring culture and a sky-navigating culture for many centuries (millennia plus technically). I see an opportunity to perhaps have a cultural center that doubles as both a center for events (cultural/spiritual) and also serve to share and preserve the ancient Polynesian stellar navigation techniques, while also providing information on the advances being done at their "top of the world".

Those thinking a telescope array is ugly, take a look at countless ridges speckled with wind turbines (which also kill MANY thousands of birds annually) - IMO, at least these instrument facilities are serving a huge public service by enhancing our knowledge. We need to make sure that this continues as much as possible. But a multi-group committee will never get much done fast. So, it may be the end of an era.

Humans have a unique and annoying capacity for extreme abstraction to the degree that something can be real when it is actually a fabrication - psychologically, and then ultimately culturally. That is where we need to get a grip as a global people. Realize what is virtual and what is not, and start to learn to decouple these - then we can make rational decisions. It may be our undoing if we don't.

I hope that the TMT does go up - but we should really focus on more space based instruments in our future, as these bear SO much more fruit without the issues surrounding our atmosphere. Maybe this is the beginning?

Best to all - I hope this is not an end to things up in Hawaii!

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September 8, 2022 at 3:26 pm

Monica Young: 34 years as a classroom teacher, I could not refrain from pointing out a typo in the title: negotation.
And since I live in Hawaii, the controversy regarding TMT has nothing to do with sacredness. Rather sacredness is being used to gain political recognition of a group of Native Hawaiians (as apposed to native Hawaiians) in order to both rewrite history and acquire control over ceded lands. The extant telescopes and the proposed Thirty Meter Telescope do not preclude sacred rituals or ceremonies on Mauna Kea. However, the oxygen deficient atmosphere at the summit certainly does.

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Monica Young

September 8, 2022 at 3:43 pm

Oh dear - thanks for pointing out the typo, fixed now!

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