(Roughly) Daily

Paul Constance on how Chile, a country riven by inequality and political conflict, has become a global sanctuary for the long science that drives astronomical discovery, and on the questions that raises…

… The next era of astronomy will depend on instruments so complicated and costly that no single nation can build them. A list of contributors to the James Webb Space Telescope, for example, includes 35 universities and 280 public agencies and private companies in 14 countries. This aggregation of design, engineering, construction and software talent from around the planet is a hallmark of “big science” projects. But large telescopes are also emblematic of the outsized timescales of “long science.” They depend on a fragile amalgam of trust, loyalty, institutional prestige and sheer endurance that must sustain a project for two or three decades before “first light,” or the moment when a telescope actually begins to gather data.

“It takes a generation to build a telescope,” Charles Alcock, director of the Harvard-Smithsonian Center for Astrophysics and a member of Giant Magellan Telescope (GMT) board, said some years ago. Consider the logistics involved in a single segment of the GMT’s construction: the process of fabricating its seven primary mirrors, each measuring 27 feet in diameter and using 17 metric tons of specialized Japanese glass. The only facility capable of casting mirrors this large (by melting the glass inside a clam-shaped oven at 2,100 degrees Fahrenheit) is situated deep beneath University of Arizona football stadium. It takes three months for the molten glass to cool. Over the next four years, the mirror will be mounted, ground and slowly polished to a precision of around one millionth of an inch.  The GMT’s first mirror was cast in 02005; its seventh will be finished sometime in 02027. Building the 1,800-ton steel structure that will hold these mirrors, shipping the enormous parts by sea, assembling the telescope atop Cerro Las Campanas, and then testing and calibrating its incommunicably delicate instruments will take several more years.

Not surprisingly, these projects don’t even attempt to raise their full budgets up front. Instead, they operate on a kind of faith, scraping together private grants and partial transfers from governments and universities to make incremental progress, while constantly lobbying for additional funding. At each stage, they must defend nebulous objectives (“understanding the nature of dark matter”) against the claims of disciplines with more tangible and near-term goals, such as fusion energy. And given the very real possibility that they will not be completed, big telescopes require what private equity investors might describe as the world’s most patient risk capital.

Few countries have been more successful at attracting this kind of capital than Chile. The GMT is one of three colossal observatories currently under construction in the Atacama Desert. The $1.6 billion Extremely Large Telescope, which will house a 128-foot main mirror inside a dome nearly as tall as the Statue of Liberty, will be able to directly image and study the atmospheres of potentially habitable exoplanets. The $1.9 billion Vera T. Rubin Telescope will use a 3.500 megapixel digital camera to map the entire night sky every three days, creating the first 3-D virtual map of the visible cosmos while recording changes in stars and events like supernovas. Two other comparatively smaller projects, the Fred Young Sub-millimeter Telescope and the Cherenkov Telescope Array, are also in the works.

Chile is already home to the $1.4 billion Atacama Large Millimeter Array (ALMA), a complex of 66 huge dish antennas some 16,000 feet above sea level that used to be described as the world’s largest and most expensive land-based astronomical project. And over the last half-century, enormous observatories at Cerro Tololo, Cerro Pachon, Cerro Paranal, and Cerro La Silla have deployed hundreds of the world’s most sophisticated telescopes and instruments to obtain foundational evidence in every branch of astronomy and astrophysics.

By the early 02030s, a staggering 70 percent of the world’s entire land-based astronomical data gathering capacity is expected to be concentrated in a swath of Chilean desert about the size of Oregon.

Collectively, this cluster of observatories represents expenditures and collaboration on a scale similar to “big science” landmarks such as the Large Hadron Collider or the Manhattan Project. Those enterprises were the product of ambitious, long-term strategies conceived and executed by a succession of visionary leaders. But according to Barbara Silva, a historian of science at Chile’s Universidad Alberto Hurtado, there has been no grand plan, and no one can legitimately take credit for turning Chile into the global capital of astronomy…

“Stumbling Toward First Light,” from @presentbias and @longnow.

* Henri Poincaré

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As we look up, we might recall that it was on this date in 2001 that NASA launched the Mars Odyssey, sending back stunning images from its tv cameras during its fiery ascent. Odyssey traveled 286 million miles before entering orbit around the red planet the following October.

Its mission was (and is– at 22-and-a-half years, it’s the longest-serving spacecraft at Mars) to use its spectrometers and a thermal imager to detect evidence of past or present water and ice, as well as study the planet’s geology and radiation environment in a quest to help answer the question of whether life once existed on Mars and to create a risk-assessment of the radiation that future astronauts on Mars might experience. (As a bonus, it acts as a relay for communications between the Curiosity rover [and previously the Mars Exploration Rovers and Phoenix lander] and Earth.)

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