Thirty Meter Telescope

Thirty Meter Telescope
An artist's rendering of proposed telescope
Alternative namesTMT Edit this at Wikidata
Part ofUS Extremely Large Telescope Program Edit this on Wikidata
Location(s)Mauna Kea Observatories, Mauna Kea, Hawaii County, Hawaii
Coordinates19°49'57.7"N, 155°28'53.8"W[1]
OrganizationTMT International Observatory
Altitude4,050 m (13,290 ft)[2]
WavelengthNear UV, visible, and Mid-IR (0.31–28 μm)
BuiltConstruction began 2014, halted since 2015
First lightTBD[3]
Telescope styleRitchey–Chrétien telescope
Diameter30 m (98 ft)
Secondary diameter3.1 m (10 ft)
Tertiary diameter2.5 m × 3.5 m (8.2 ft × 11.5 ft)
Mass2,650 t (2,650,000 kg) Edit this at Wikidata
Collecting area655 m2 (7,050 sq ft)[2]
Focal lengthf/15 (450 metres [1,480 ft])[2]: 52 
MountingAltazimuth mount
EnclosureSpherical calotte
WebsiteTMT.org
Thirty Meter Telescope is located in Hawaii
Thirty Meter Telescope
Location of Thirty Meter Telescope
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The Thirty Meter Telescope (TMT) is a planned extremely large telescope (ELT)[5][6][7] proposed to be built on Mauna Kea, on the island of Hawai'i. The TMT would become the largest visible-light telescope on Mauna Kea.[8][9]

Scientists have been considering ELTs since the mid 1980s. In 2000, astronomers considered the possibility of a telescope with a light-gathering mirror larger than 20 meters (66 ft) in diameter, using either small segments that create one large mirror, or a grouping of larger 8-meter (26 ft) mirrors working as one unit. The US National Academy of Sciences recommended a 30-meter (98 ft) telescope be the focus of U.S. interests, seeking to see it built within the decade.

Scientists at the University of California, Santa Cruz and Caltech began development of a design that would eventually become the TMT, consisting of a 492-segment primary mirror with nine times the power of the Keck Observatory. Due to its light-gathering power and the optimal observing conditions which exist atop Mauna Kea, the TMT would enable astronomers to conduct research which is infeasible with current instruments. The TMT is designed for near-ultraviolet to mid-infrared (0.31 to 28 μm wavelengths) observations, featuring adaptive optics to assist in correcting image blur. The TMT will be at the highest altitude of all the proposed ELTs. The telescope has government-level support from several nations.

The proposed location on Mauna Kea has been controversial among the Native Hawaiian community.[10][11][12][13] Demonstrations attracted press coverage after October 2014,[14] when construction was temporarily halted due to a blockade of the roadway. When construction of the telescope was set to resume, construction was blocked by further protests each time.[15] In 2015, Governor David Ige announced several changes to the management of Mauna Kea, including a requirement that the TMT's site will be the last new site on Mauna Kea to be developed for a telescope.[16][17] The Board of Land and Natural Resources approved the TMT project,[18][19] but the Supreme Court of Hawaii invalidated the building permits in December 2015, ruling that the board had not followed due process. In October 2018, the Court approved the resumption of construction;[20] however, no further construction has occurred due to continued opposition. In July 2023 a new state appointed oversight board, which includes Native Hawaiian community representatives and cultural practitioners, began a five-year transition to assume management over Mauna Kea and its telescope sites, which may be a path forward.[3] In April 2024, TMT's project manager apologized for the organization having "contributed to division in the community", and stated that TMT's approach to construction in Hawai'i is "very different now from TMT in 2019."[21]

An alternate site for the Thirty Meter Telescope has been proposed for La Palma, Canary Islands, Spain, but is considered less scientifically favorable by astronomers.[22] As of March 2024, there were no specific timelines or schedules regarding new start or completion dates.[citation needed]

  1. ^ Sanders, Gary H. (January 11, 2005), [79.03] The Thirty Meter Telescope (TMT) Project (PDF), p. 17, archived from the original (PDF) on July 19, 2011
  2. ^ a b c d Thirty Meter Telescope Construction Proposal (PDF), TMT Observatory Corporation, September 12, 2007, p. 29, archived from the original (PDF) on March 24, 2016, retrieved July 24, 2009
  3. ^ a b Cite error: The named reference zastrow was invoked but never defined (see the help page).
  4. ^ "Thirty Meter Telescope Selects Mauna Kea". TMT Observatory Corporation. July 21, 2009. Archived from the original on September 1, 2014. Retrieved July 24, 2009.
  5. ^ Overbye, Dennis (March 8, 2024). "Good News and Bad News for Astronomers' Biggest Dream - The National Science Foundation takes a step (just one) toward an "extremely large telescope."". The New York Times. Archived from the original on March 8, 2024. Retrieved March 8, 2024.
  6. ^ Perryman, Michael (August 31, 2018). The Exoplanet Handbook. Cambridge University Press. p. 345. ISBN 978-1-108-32966-8.
  7. ^ Govert Schilling; Lars Lindberg Christensen (December 7, 2011). Eyes on the Skies: 400 Years of Telescopic Discovery. John Wiley & Sons. p. 45. ISBN 978-3-527-65705-6.
  8. ^ "What is TMT?". TMT International Observatory. Retrieved July 27, 2019.
  9. ^ Jones, Caleb (June 20, 2019). "Controversial telescope to be built on sacred Hawaiian peak". AP News. Associated Press.
  10. ^ "'We put everything into it.' Modest telescope could have big impact on Turkish science". Science. March 4, 2020.
  11. ^ "Controversy over giant telescope roils astronomy conference in Hawaii". Space.com. January 16, 2020. Retrieved February 13, 2020.
  12. ^ "Why are Jason Momoa and other Native Hawaiians protesting a telescope on Mauna Kea? What's at stake?". USA today. August 21, 2019.
  13. ^ "'This is our last stand.' Protesters on Mauna Kea dig in their heels". CNN. July 22, 2019.
  14. ^ Herman, Doug (April 23, 2015). "The Heart of the Hawaiian Peoples' Arguments Against the Telescope on Mauna Kea". Smithsonian.com. Smithsonian.com. Retrieved May 3, 2015.
  15. ^ Cite error: The named reference restart was invoked but never defined (see the help page).
  16. ^ "Governor David Ige announces major changes in the stewardship of Mauna Kea". Governor of Hawaii. May 26, 2015. Retrieved January 16, 2020.
  17. ^ "UPDATE: Notice to Proceed Granted for Thirty Meter Telescope | Big Island Now". Big Island now. June 20, 2019. Retrieved August 24, 2019. We also accept the increased responsibilities for the stewardship of Maunakea, including the requirement that as this very last site is developed for astronomy on the mauna, five current telescopes will be decommissioned and their sites restored."
  18. ^ "Construction Permits Revoked on the Thirty-Meter Telescope in Hawaii". Archived from the original on December 12, 2015. Retrieved October 21, 2015.
  19. ^ Cite error: The named reference news1 was invoked but never defined (see the help page).
  20. ^ "Hawaii top court approves controversial Thirty Meter Telescope". BBC News. October 31, 2018.
  21. ^ Brestovansky, Michael. "TMT project manager admits past mistakes, notes project is dependent on NSF funding, support from Hawaiians". Hawaii Tribune-Herald. Retrieved July 13, 2024.
  22. ^ "Stalled in Hawaii, giant telescope faces roadblocks at its backup site in the Canary Islands". www.science.org. Retrieved March 14, 2023.