Witnessing the birth of a star or the early days of a galaxy is all about distance. The further out a telescope peers into space, the better for astronomers hoping to glimpse the early universe.

An international group of astronomers plan to do just that with one of the largest radio telescopes ever to be constructed. The new tool, an array or more than five dozen radio antennas pointed skyward, will monitor cosmic emissions bordering the microwave and infrared wavelengths that may even allow researchers to see the formation of organic molecules in space.

"ALMA will be the first large-scale millimeter telescope in the world," said Charles Blue, spokesman for the National Radio Astronomy Observatory (NRAO), in a telephone interview. The observatory is coordinating North American involvement in the project, including Canada as well as the U.S., for the NSF.

The new observation tool will consist of an array of 40-foot (12-meter) radio telescopes, 64 in all, each linked together to make up the world's largest radio telescope to observe at millimeter and submillimeter wavelengths. Emissions at these levels have wavelengths longer than infrared, but shorter than radio waves and aren't visible by the naked eye.

Astronomers began testing a prototype telescope for ALMA at the Very Large Array (VLA) in Socorro, New Mexico earlier this year. That 12-meter dish gained first light in mid-January, with ALMA researchers awaiting a second version - this one from the ESO - to be installed for testing sometime in July.

"We'll be testing and characterizing both instruments, leading up to the final selection of a standard telescope for ALMA," radio astronomer Richard Simon told SPACE.com. Simon has spent the last five years with the NRAO planning for the new telescope array's construction. "We're scheduled to break ground on the entire project by the end of the year."

Radio astronomers hope ALMA's capabilities will push aside the veil on the earliest days of the universe and allow for detailed observation of galaxy formation. The array is expected to resolve distant objects at least five to 10 times better than the Hubble Space Telescope or the VLA.

"ALMA will be on the lookout as far back in time as you possibly can reach," Simon said, adding that the instrument could detect protogalaxies, a cauldron of stars and gas in the midst of becoming a full-fledged galaxy. "We expect that it will be able to detect signatures from planets as they form and stars as they collapse and condense from an accretion of gas."

Large, hot extrasolar planets - like those on the scale of Jupiter in size - may even be observed directly, rather than watching the wobble of a star as it moves. The "wobble" method infers the existence of an extrasolar planet by the gravitational effect it has on a parent star.

While optical telescopes can be constrained by the amount of visible light detected, ALMA should see through interstellar dust to observe the emissions emanating from the interior of interstellar clouds of gas.

Since organic molecules like ethanol tend to reside inside gaseous clouds, with temperatures of about 10 degrees Kelvin (-263 degrees Celsius), ALMA researchers should be able to detect them and use the observations to learn about the cloud's internal composition and motion through space, Simon said.

The array is also expected to pinpoint objects 10 milliarcseconds wide in the sky. Arcseconds are the measuring tool astronomers use to find the size of an object in space, with 60 arcseconds in one arcminute and 60 arcminutes in one degree. The full moon, for example, is about the equivalent of 30 arcminutes.

ALMA should also monitor a range of interstellar emissions ranging in wavelengths from 3 millimeters at maximum on down to one-third of a millisecond. There should be little overlap between the new array and NRAO's other large interferometry instruments, such as the VLA, because of the wavelengths ALMA will monitor.

"There won't be almost any overlap at all there," Blue said. "The VLA primary makes observations at the centimeter level, but ALMA will be a great additional tool."

The sheer size of the array, however, will outstrip its current submillimeter counterparts in France, California and Hawaii, each of which sports only a handful of radio telescopes working together. Not only will ALMA be peering out into the Southern Hemisphere - the others are all north of the equator - but its more sensitive receiver, wider bandwidth capacity and better vision put it spades in front of submillimeter arrays in use today. The researchers at those arrays, though, also have also a hand in ALMA's development.

"We're collaborating with those groups on some of the computing and calibration issues for the new array," Simon said.

One of the keys to ALMA's expected performance lies in its Chilean home. The location chosen for the new telescope is near Cerro Chajnantar in the Atacama Desert, about 16,500 feet (about 5,000 meters) above sea level. Since most emissions in the millimeter and submillimeter range are absorbed by moisture in the atmosphere, the arid high-altitude desert environment is crucial for ALMA researchers.

"One of the challenges of observing at the submillimeter wavelength is that the atmosphere is not your friend," Simon said. "The [ALMA site] is an unbelievable place, with huge, flat terrain and clarity of the air up there that is what you'd expect from a mountain region."

ALMA planners rejected potential sites in the southwest United States and atop Hawaii's Mauna Kea, home of the Keck Observatory, before settling for the Atacama location, he added.

The area is no stranger to telescopes, either. A pair of ESO observatories - Paranal and La Silla - make observations from there and engineers are planning to use the area as the future site for the Overwhelmingly Large Telescope, or OWL. That telescope would be ALMA's optical cousin, and secure the title of world's largest optical telescope with a 109-yard (100-meter) aperture.