In a moment long-awaited by thousands of astronomers from around the globe, a cluster of precision radio telescopes located on the barren Chajnantor Plateau of northern Chile has finally gone operational. Although only partially complete, ALMA, or the Atacama Large Millimeter/submillimeter Array, is already considered the most advanced telescope of its type. Certainly, it's the highest, with a literally breath-taking base elevation of 16,500 feet (5000m).

"We went to one of the most extreme locations on Earth to build the world's largest array of millimeter/sub-millimeter telescopes, having a level of technical sophistication that was merely a dream only a decade ago," said Dr. Mark McKinnon, Project Manager of the North American ALMA program at the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia.

With 19 antennas currently deployed, the internationally-funded $1.3 billion ALMA will eventually (at completion in 2013) boast a total of 66 individual, fiber optic-linked, portable, 40-foot diameter, 115-ton radio telescopes, all functioning as one, and will cover an area of roughly 100 square miles. The massive amounts of data gathered by the array will be digested and assembled into single images by a supercomputer churning away at a blistering 17 quadrillion operations a second.

"The 'M' in ALMA stands for 'millimeter/submillimeter' waves, because ALMA views the Universe in these long wavelengths of light, much longer than the optical light we see with our eyes," said Dr. Alison Peck, an NRAO astronomer serving as ALMA Deputy Project Scientist during construction.

"With millimeter and submillimeter waves, we can watch planet formation, investigate astrochemistry and detect the light that is finally reaching us from the universe's earliest galaxies. ALMA's first projects will flex the telescope's capabilities in all of these fields and many, many more."

To lend additional flexibility to the array, the individual antennas can be moved around to suit specific project needs, using specially-designed ALMA 'transporter' vehicles.

The facility kicked off a nine month Early Science phase of operations with the release of ALMA's first image for public scrutiny: the two colliding spiral Antennae Galaxies (NGC 4038 and 4039), nearly 70 million light-years away in the distant Corvus constellation. It yields details that traditional optical and infrared telescopes simply can't see. As more antennas come online, scientists expect the array to yield increasingly sharper images.

Judging from the overwhelming response of the scientific community, with nearly a hundred projects already scheduled for time on the array, ALMA has hit the ground running. "We were stunned when we received over nine hundred requests from all over the world!" said Dr. Lewis Ball, ALMA Deputy Director and NRAO's ALMA Chief of Staff.

"No other telescope on ground or in space has ever had this magnitude of over-demand."

The observatory is administered by a partnership of various agencies from Europe, Japan and North America, in cooperation with the Chilean government.

The NRAO video below provides an overview of the project.

Sources: NRAO, ALMA