Chilean desert: new astronomy capital of the world

Back when she lived in the rural stretches of northern Chile, Ileana Cortés spent few evenings watching television.

"The best entertainment was looking up into the skies," says the amateur astronomer, recalling the star clusters she regularly sought out – the Magellanic Clouds, Orion's Belt, the Southern Cross. "Chile's heavens are privileged," she says.

Space-based telescopes such as the Hubble and land-based ones in Hawaii may be better-known centers of astronomical study. But with consistently clear skies, northern Chile is one of the best windows on Earth to the stars and home to several world-class telescopes.

Astronomy in Chile is ready for the world's stage: A new optical telescope is up and running. Enhancements on another are nearly done, which will make it the world's largest, and plans are advancing to build one of the biggest radio telescopes ever.

The projects herald "a golden age of astronomy," says Malcolm Smith, director of the Cerro Tololo Inter-American Observatory near the northern city of La Serena. "It's a marvelous time to be an astronomer."

Last May, astronomers at the California Institute of Technology said a two-year-old radio telescope high in the Chilean Andes detected radiation waves from nearly 14 billion years ago, adding credence to the Big Bang theory of the universe's creation.

With the new generation of telescopes, more landmark discoveries are waiting to happen, astronomers say.

"We'll be able to see things we've never seen before," says Chilean astronomer Eduardo Hardy, speaking of the planned Atacama Large Millimeter Array radio telescope (ALMA), which will link 64 39-foot antennas when fully operational in 2011. "It will revolutionize the study of formation of galaxies and stars."

The new devices will also help identify planets in other solar systems, assist in the search for life on other planets, and help determine the size, shape, and other details of the universe, astronomers say.

The Chilean Tourism Ministry has even gotten in on the act, pushing travel along the so-called "Route of the Stars," which links northern Chile's various observatories. As part of that effort, local authorities have opened amateur viewing facilities, like the Mamalluca Observatory outside the northern town of Vicuña.

The arid, cloud-free climate of northern Chile, home to the Atacama Desert, the driest in the world, is ideal for stargazing. Taking advantage of the conditions, several world-class observatories started operating here in the 1960s, including Cerro Tololo, built by the US National Science Foundation (NSF), and La Silla, built by the European Southern Observatory (ESO).

In January an NSF-led consortium inaugurated Gemini South, a mammoth, silver-domed structure nearly 9,000 feet up amid the rocky scrub east of La Serena. With its infrared detectors and 27-foot mirror, Gemini South associate director Phil Puxley says it is the premier telescope for observing cooler astronomical bodies like failed stars and super planets, which are bigger than planets but smaller than stars.

ESO, a consortium of eight European nations, built the Very Large Telescope (VLT), actually four telescopes with 27-foot mirrors, north of La Serena in the Atacama Desert in 1999. Work continues to connect the mirrors to create a device with the power of a 52.5-foot telescope. When completed this year, it will become the world's most powerful optical telescope, eclipsing Hawaii's Keck Observatory.

"You'll be able to see a man on the moon," says Estaban Illanes, an ESO spokesman.

Construction of ALMA on a 16,500-foot plateau in the Atacama Desert will start next year, with preliminary observations by 2006. When fully operational in 2011, its 64 antennas will let astronomers peer through the otherwise impenetrable layer of cosmic dust and gas that typically enshrouds galaxies and stars still in formation to see how such bodies evolve.

"It opens a window into the universe," says Hardy, the US representative in Chile for the multinational project.

Looking into the future, the ESO is studying the feasibility of an optical telescope with a mirror measuring 328 feet, possibly to be built in Chile. With such a big telescope, called the Overwhelmingly Large Telescope, Puxley says astronomers would be able to make comprehensive studies of every star in the Milky Way.

Smith says such a telescope is a long way off, but maintains that the possible discoveries going forward are limitless.

"It's going to be an extremely exciting and productive time," he says.