HONOLULU (AP) – When starlight from billions of years ago sweeps through the universe and finally comes into focus on Earth, astronomers want their telescopes to be in the best possible locations to see what’s out there.
Despite years of litigation and months of protests from local Hawaiian opponents, the international coalition to build the world’s largest telescope in Hawaii insists that the islands’ tallest peak – Mauna Kea – is the best place for their $ 1.4 billion -Instrument is.
But only barely.
Officials of the thirty-meter telescope admit that their backup location on a summit on the Spanish Canary Island of La Palma is a comparable observatory location and that it would not cost more money or additional time to build it there.
There is also no significant resistance to placing the telescope on La Palma, as is the case in Hawaii, where some indigenous Hawaiians consider the mountain sacred and prevented trucks from bringing construction equipment to the summit of Mauna Kea for more than a month to transport.
But Hawaii has perks that scientists say they do a little better: higher altitudes, cooler temperatures, and rare moments of stargazing that allow the state-of-the-art telescope to reach its full potential.
“On Mauna Kea you experience one of these magical nights every now and then,” said Michael Bolte, professor of astronomy and astrophysics at the University of California, Santa Cruz, board member of the thirty-meter telescope. “When the air over the site is super stable, you get pictures that you can’t get anywhere else.”
Bolte, who used pre-existing Mauna Kea telescopes, said these “magical” Hawaiian nights could contain discoveries that might be overlooked on La Palma.
“Suppose one of your great scientific cases is looking for life on planets orbiting other stars,” he said. “The star is so much brighter than the planet you want to observe, it’s really hard.”
The advanced optics and enormous size of the thirty-meter telescope, especially if it is built at the higher elevation of Mauna Kea, could allow scientists to more easily discover planets potentially filled with life, Bolte said.
To see distant planets near bright stars, astronomers use telescopes to capture infrared light emanating from space objects.
But John Mather, an astrophysicist who won the 2006 Nobel Prize in Physics for his work on the Big Bang theory, says there are other ways to get this data.
Mather, lead project scientist for NASA’s James Webb Space Telescope, due to launch in 2021, said the new instrument will be extremely effective at collecting infrared light. The atmosphere will not hinder the telescope’s imaging capabilities because it is not on Earth.
Data from the Webb telescope can be combined with information from other earth-based telescopes to compensate for the infrared advantage of Mauna Kea over La Palma, said Mather.
He said Webb will “open up new territory that you can never tackle from the ground”.
Mather is also working on a longer-term solution to the problem of seeing Earth-like planets in orbit around distant stars, which he compared to a “glow worm next to a headlight”.
It is a large “star screen” that is shot far into space and positioned to block bright stars while telescopes on Earth can see the planets orbiting them.
These advances could level the playing field between places like Mauna Kea and La Palma, said the astrophysicist Avi Loeb, who heads the astronomy department at Harvard University.
“You have to remember that people can change the system to compensate for the somewhat worse conditions,” Loeb said in Spain. “In the end, it might do as well, or maybe even better.”
Loeb agreed that Mauna Kea is a slightly better place for infrared observations. But La Palma was “an excellent place, so extraordinary science would be carried out there,” he added.
The opponents of the Indian Hawaiians call themselves “protectors” of Mauna Kea and are not worried about the advantages of their mountain for astronomers. They just want the telescope group to leave Hawaii.
That would be “a win for everyone,” said protest leader Kealoha Pisciotta, shortly after officials of the thirty-meter telescope had announced that they would apply for a building permit for the site on La Palma a few weeks ago.
“There is a lot of good science to be done in the Canary Islands,” said Pisciotta.
Not all indigenous Hawaiians are against the telescope. Some advertise the educational and business opportunities it would bring to the Big Island. Others have compared modern astronomers to their Polynesian ancestors, who used stars to navigate their wooden booms across the Pacific and discover new lands – including Hawaii.
Mauna Kea is nearly 4,300 meters above sea level, more than twice as high as the Spanish site, which is already home to the largest optical telescope in the world. Like Hawaii’s Big Island, Spain has good weather, a stable atmosphere, and very little light pollution.
The thirty-meter telescope would be a next-generation model designed to transform ground-based astronomy – and enable scientists to see deeper into space than was previously possible. Its large mirror creates sharper and more detailed images of space.
“You can get images that are 12 times sharper than the Hubble Space Telescope,” said Bolte.
And most of the scientific work planned for Hawaii would still be done in Spain – it would just take longer.
“Depending on the type of science you want to do, the speed will be anywhere from 10% to 50%,” said Bolte. “You have to watch so much longer on La Palma to get the same quality data.”
José Manuel Vilchez, astronomer of the Spanish Supreme Council for Scientific Research and a former member of the scientific committee of the Astrophysical Institute of the Canary Islands, said the construction of the telescope on La Palma was not a downgrade.
“We speak of the best of the best. One is a 10, the other a 9.9, ”said Vilchez. “We’re talking about decimal numbers.”
But for astronomers, decimals can make all the difference between seeing something extraordinary or missing it.
“The Mauna Kea, because it is higher, would have a thinner atmospheric layer and would observe more in certain infrared regions,” said Vilchez. “The possibility to capture the picture is less” on La Palma.
Vilchez also said that there is more public support for the telescope in Spain and that the cost of running it at a lower altitude would be cheaper.
On Mauna Kea, “you are further from the base and the costs are increasing,” said Vilchez. “In the Canary Islands the institutional support is 100% and 99% of the citizens support the astronomy work.”
The officials cannot claim this lack of opposition for Mauna Kea.
Bolte of the Telescope Group said what began as opposition to the project has “become the focus of the entire Hawaiian sovereignty and self-determination movement” and reflects how Native Hawaiians have felt “displaced from their own lands” for over a century.
“Now that you have everyone’s attention by stopping this telescope, how can that be used to somehow take some steps for the benefit of the indigenous Hawaiians?” he asked.
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Associate press writer Joseph Wilson in Barcelona, Spain contributed to this report.
