August 25, 2007
Telescope in Mexico to Look for Dawn of Universe
By Jane Bussey, The Miami Herald
SIERRA NEGRA, Mexico -- On this windswept peak where visitors gasp in the thin air, Mexico is building the world's largest telescope of its kind, an instrument primed to be powerful enough for scientists to look back at the dawn of the universe.The Large Millimeter Telescope, located on the summit of the dormant volcano Sierra Negra, is considered Mexico's most ambitious scientific project ever. It is also currently the biggest scientific collaboration between the United States and any Latin American country.
Nine years after construction began, the telescope is now some nine months away from its first attempts at capturing images from faint millimeter waves, a type of radio wave. Scientists calculate these have been traveling through space since shortly after the Big Bang, some 13.4 billion years ago.
"Some people talk about telescopes like time machines," said Peter Schloerb, a University of Massachusetts astronomy professor who is the U.S. director of the project. "You can see objects in the universe as they were billions of years ago, just a few hundred thousand years after the Big Bang, when [the universe] was a big, hot ball of plasma."
The telescope's size -- 164 feet in diameter -- plus advances in technology make this feat possible.
Radio receivers and computers will transform the millimeter waves into pictures of the universe, including images from the cold gas clouds where stars are formed.
The telescope is a joint project between Mexico's National Institute of Astrophysics, Optics and Electronics and the University of Massachusetts at Amherst, whose astronomy department is a leader in this particular field.
The lofty goals of this joint effort are matched by the monumental challenges of building a telescope in the inhospitable environment atop the 15,000-foot Sierra Negra volcano.
The location offers low humidity and a latitude that allows it to view the southern and northern skies, ideal for this type of telescope, but the lack of oxygen leaves most visitors tired and short of breath.
"There are people who fainted when they got here," said telescope technician Francisco Martinez.
The telescope rests on a concrete base. It can turn a full circle and tilt up to 180 degrees to face different areas in the sky. Living quarters, laboratories and control rooms are located in the foundation.
Even before pouring the first concrete, crews had to build a road up the mountain, 20 switchbacks in all. To determine the location, organizers sent mules down the mountain -- then built the road along the path they took.
Another challenge: lifting the 460-ton telescope reflector dish onto its base, a task requiring two 1,000-ton cranes. Mexico had only one crane that large, and it was being used on a freeway construction project. Organizers had to buy a second crane and wait until the first was available to put the antenna reflector into position in late 2005.
Now scientists and technicians are installing and adjusting the 180 reflector panels that form five rings on the surface of the giant dish. The adjustment must be done with absolute precision; the margin of error is less than half the width of a single hair. The panels must be adjusted and re-adjusted before the first trials of three out of the five rings can start.
"This is a mega-project," said Fernando Correa, who handles the transportation logistics.
Fearful that vibrations from Mexico's bumpy roads could damage the panels, the project installed stabilizing platforms on the trucks, using an invention that had previously won its inventors a national technology prize, Correa said.
Overcoming these challenges has made the telescope a source of national pride. Mexico spends less than half of 1 percent of its gross domestic product on science and technology, and large numbers of its scientists are part of the "brain drain" to the developed world.
"People thought we couldn't do it," Martinez told visitors, including Mexico City-based members of the Association of University Engineers who have trekked to the telescope three times.
The telescope has cost $130 million including more than $40 million from the University of Massachusetts and other U.S. sources. Delays, rising costs and scarce funds have plagued the effort.
Alfonso Serrano Perez-Grovas, former director of the Institute of Astrophysics and future director of the Large Millimeter Telescope Observatory, is credited with persuading numerous administrations of the project's importance and raising money, even helping to stage a rock concert in Mexico City to raise private funds.
Schloerb called Serrano the "driving force" behind the Large Millimeter Telescope. "We would never have gotten anywhere without him," he said, adding that Mexico has a lot riding on its completion.
"It is really a major undertaking for Mexico, and we appear to be closing in on success," said Schloerb, who received his doctorate from the California Institute of Technology.
The United States -- along with the European Southern Observatory, Spain, Canada, Japan and Chile -- are involved in an even bigger project, the Atacama Large Millimeter Array, being built in the Chilean Andes and scheduled to be completed in 2012.
That telescope, called ALMA, is a $1 billion-plus project that will consist of 54 to 60 millimeter wave telescopes, each 12 meters or 39 feet in diameter.
ALMA will produce finer resolution pictures of the sky, Schloerb said. But the Large Millimeter Telescope will be able to map the sky faster.
Serrano is not only sure the telescope will shed light on the cold, dense and obscured areas of the universe but that it will lead to knowledge about the birth of stars and extra-solar planets, among other cosmic questions.
He also believes the project will contribute to the development of Mexico, where he returned after finishing his doctorate at the University of Sussex because he felt he could make a bigger contribution.
"When [the telescope] was inaugurated," Serrano said, "My three emotions were relief, gratitude for all the thousands of people who have helped . . . and pride because we are doing something so important that is going to allow us to discover a universe we don't know -- and Mexicans are going to do it."
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