Inauguration of the ALMA telescope [fr]

The largest radiotelescope in the world—Atacama Large Millimeter/submillimeter Array (ALMA)—was inaugurated on Wednesday, March 13, 2103. The telescope is located at an altitude of 5000m on the Atacama Plateau in the Chilean Andes. This telescope, the largest astronomical project ever constructed on solid ground, is the result of collaboration between 17 countries, including France and Canada.

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Chajnantor plateau
On the Chajnantor plateau, one can already observe half of the 66 permanent antennas that will comprise the ALMA observatory when it is completed in late 2013.
ALMA (ESO/NAOJ/NRAO), C. Padilla

66 eyes on the cosmos



ALMA is the largest radiotelescope ever built, revolutionary in its scientific concept, its construction, and its global scale. The telescope is made up—for the moment—of 66 high-precision antennas ranging from 7 to 12 meters in diameter spread out over 200 square kilometres, all working together to cover the millimetric and sub-millimetric wavelengths.
ALMA’s resolution and sensitivity are unparalleled, according to Laurent Vigroux, the director of the Institut d’astrophysique in Paris. When ALMA’s antennas are arranged in their compact configuration, the instrument—with a total surface area of 7000 m2—will be almost ten times more sensitive than the current most powerful radiotelescope in the world: the one at Bure, in France’s Haute-Alpes. In ALMA’s expanded configuration, where some of the antennas will be up to 16 kilometres from the others, the resolution of its images will reach 0.01 arcseconds, compared to 0.3 arcseconds in Bure!


Ambitious expectations



ALMA is opening extraordinary doors for astrophysicists in terms of the study of millimetric and submillimetric radiation—in other words, far-infrared: the part of the light spectrum corresponding to the cold phenomena of the universe. This exceptional equipment will also allow scientists to explore the chemistry of interstellar space, where complex organic molecules form, particularly the amino acids that make up the building blocks of life. The radiotelescope’s eyes will also be an invaluable way for scientists to make out the oldest of galaxies, formed when the Universe was only a billion years old.
Even though only 16 antennas are functioning at the moment, encouraging results have already been achieved, including the fact that astrophysicists have already been able to draw up the most precise map to date of the dynamic gases surrounding a star. These results were published in Nature.

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Flows of gas through a protoplanetary gap (artistic view)
ALMA (ESO/NAOJ), S. Casassus, et al.


The unparalleled sensitivity and high-resolution capabilities of ALMA also open up new opportunities for scientists to delve into the primordial secrets of the universe and to go back to its very origins, tracking the first stars and galaxies and exploring exoplanets for the first traces of life. ALMA expects to make incredible astronomical discoveries, but it’s still too soon to tell what discoveries these might be…


The sun doesn’t set on ALMA



Built by a consortium covering four continents, the project brings together the thirteen countries of the European Southern Observatory (ESO), of which France is one of the founding countries, with such other countries as Canada, the United States, Japan, and Taiwan.
The participation of France and Canada in this project confirms their international status as leaders in astronomy. France has also invested in the very recent European Extremely Large Telescope (EELT) and the Very Large Telescope (VLT). Canada, whose involvement in the ALMA project through the CNRC—very recently announced the construction of the largest radiotelescope in Canada [in French], in Penticton, British Colombia.
Visit the ALMA site for more information.


Article posted on March 21st, 2013

Dernière modification : 21/07/2016

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