The Bure plateau, in the heart of the Dévoluy massif (Hautes-Alpes), is an exceptional place. And the presence of the NOEMA observatory (for Northern Extended Millimeter Array) adds a little more atmosphere to this high-perched place – 2,500 meters above sea level. NOEMA, these are 12 huge parabolas 15 meters in diameter (for 130 tons each!) and mounted on rails to be able to move them on two perpendicular axes. The 12th was recently installed and the observatory is now reaching its maximum capacity.
“We observe simultaneously with the 12 antennas, strictly the same position in the sky – the same star or the same galaxy, explains Frédéric Gueth, deputy director of IRAM, a structure funded by the French CNRS, the German Max-Planck Institute, and the Spanish IGN. The goal of the game then is to combine the signals observed by these 12 antennas to create a signal that would have (in the conditional) observed by a single antenna whose diameter would have the distance between our antennas. If we put ourselves in a configuration where there is 1.7 km distance between the antennas, well we are going to simulate what a giant radio telescope – which does not exist! – 1.7 km in diameter would have observed.
Observe the edges of the Universe
In fact, NOEMA is therefore the most powerful radio telescope in the Northern Hemisphere. If thanks to it we can study the details of nearby celestial objects, we can also push up to 10, 11 or 12 billion light-years… that is to say we can go back in time and observe what happened shortly after the formation of the universe.