Atacama

Atacama desert

In the background we can see the heart of our Galaxy full of gas and dust, star clusters and emission nebulae, as well as the orange star Antares from Scorpius constellation and the dark dust that conects this region to the main arm of Milky Way. Below, in the foreground of this same region, a faint white light called the Zodiacal Light is very well visible, coming up as a backlight behind the antenna of ALMA (DV-21) with12 meters in diameter, is capturing the wavelengths from vast cold clouds in the interstellar space. This are the first tests to experiment the largest configuration that ALMA can support, with antennas spreaded over distances up to 16 km. The array thus simulates a giant, single telescope much larger than any that could actually be built. In fact, ALMA has a maximum resolution which is even better than that achieved, at visible wavelengths, by the Hubble Space Telescope.

The Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of radio telescopes in the Atacama desert of northern Chile. Since a high and dry site is crucial to millimeter wavelength operations, the array has been constructed on the Chajnantor plateau at 5,000 meters altitude, near Llano de Chajnantor Observatory and Atacama Pathfinder Experiment. Consisting of 66 12-meter (39 ft), and 7-meter (23 ft) diameter radio telescopes observing at millimeter and submillimeter wavelengths, ALMA is expected to provide insight on star birth during the early universe and detailed imaging of local star and planet formation.

ALMA is a single telescope of revolutionary design, composed initially of 66 high-precision antennas, and operating at wavelengths of 0.32 to 3.6 mm. Its main 12-metre array has fifty antennas, 12 metres in diameter, acting together as a single telescope — an interferometer. An additional compact array of four 12-metre and twelve 7-metre antennas complements this. The 66 ALMA antennas can be arranged in different configurations, where the ma