Rival giant telescopes join forces to seek U.S. funding

[Judi Lynn]

A technician prepares chunks of glass prior to spin-casting one of the seven 8-meter mirrors for the Giant Magellan Telescope. GIANT MAGELLAN TELESCOPE–GMTO CORPORATION

Rival giant telescopes join forces to seek U.S. funding
By Eric HandMay. 21, 2018 , 12:00 PM

Two U.S.-led giant telescope projects, rivals for nearly 2 decades, announced today that they have agreed to join forces. The Giant Magellan Telescope (GMT), a 25-meter telescope under construction in Chile, and the Thirty Meter Telescope (TMT), which backers hope to build atop Mauna Kea in Hawaii, have not finished acquiring the necessary partners and money. They will now work together to win funding from the National Science Foundation (NSF) in Alexandria, Virginia, which could help the projects catch up to a third giant telescope, the 39-meter European Extremely Large Telescope (ELT), due to begin operations in 2024. It is a historic peace accord to end a conflict that has divided funders and delayed both projects.

“This division has set back U.S. astronomy a decade,” says Richard Ellis, an astronomer at University College London, and a former leader of the TMT effort. “Let’s turn the corner.” Patrick McCarthy, a GMT vice president in Pasadena, California, adds, “It’s time for these two projects to come together behind a single vision.”

The partnership, approved by the GMT board this month and by the TMT board last month, commits the two projects to developing a joint plan that would allow astronomers from any institution to use the telescopes; under previous plans observing time was available only to researchers from nations or institutions that had provided funding. The projects are discussing awarding at least 25% of each telescope’s time to nonpartners through a competitive process to be administered by the National Center for Optical-Infrared Astronomy—an umbrella organization that will replace the National Optical Astronomy Observatory (NOAO), based in Tucson, Arizona, sometime in fiscal year 2019. Telescope backers hope the public access plan will help persuade the federal government to pay for at least 25% of the total cost of the two facilities, which could total $1 billion. (Cost estimates for the GMT and the TMT are $1 billion and $1.4 billion, respectively, but astronomers expect both numbers to grow.) “There are many science projects that are $1 billion class projects,” says David Silva, NOAO’s director. “The investment that we would want is of a similar size.”

Advocates for the TMT and the GMT “missed opportunities” to unite astronomers, lawmakers, and funding agencies around a single telescope in the early 2000s, Ellis says. Instead, the projects diverged. The TMT began in 2002 under the leadership of the California Institute of Technology in Pasadena and the University of California system. To make a giant mirror that wouldn’t deform under its own weight, the TMT’s partners looked for inspiration in a fly’s eye, fragmenting the main 30-meter mirror into nearly 500 small, 1.4-meter hexagonal pieces, each individually adjustable. The GMT, initially led by the Carnegie Observatories in Pasadena, has seven larger segments, each 8 meters across. They are made of stiff, lightweight glass, cast in molds that spin as the glass cools to bring it into a parabolic shape. In 2005, the GMT cast the first of its mirrors, and the divergent technological paths were set.

More:
http://www.sciencemag.org/news/2018/05/rival-giant-telescopes-join-forces-seek-us-funding

Also in Science:
https://www.democraticunderground.com/122857453

[longship]

1. One still needs two large telescopes, one north, and one south.

The northern sky is different from the southern sky.

The choice place in the north is Mauna Kea, and no where else comes remotely close. There are many locations in the Southern Hemisphere due to the Andes.