A mission to study the dark side of the universe

ESA’s Euclid mission, designed to explore the dark side of the universe, has already entered the construction phase. This mission was selected in October 2011 together with Solar Orbiter as one of the first two M-class missions of theCosmic Vision 2015-2025 program of the agency. The committee has agreed to draft a memorandum of understanding between ESA and NASA through which the US space agency will collaborate on the mission by providing the infrared detectors.

Euclid will be equipped witha 1.2 meter diameter telescope, and his two instruments will make athree-dimensional map of the distribution of up to two billion galaxies, and the dark matter they contain, which according to current theories could constitute up to a third of the mass of the universe. Spanning more than ten billion light-years, this mission will study the evolution of the structure of the universe over three-quarters of its history.

Euclid has been designed to find answers to one of the most important questions in modern cosmology:why the universe is expanding at an accelerated rate, instead of slowing down under the gravitational action of the matter it contains? The discovery in 1998 of this cosmic acceleration was awarded the Nobel Prize in Physics in 2011, although its causes are still unknown.

The term“dark energy”is used in this context to designate thismysterious force that accelerates the expansion of the cosmos. By using Euclid to study its effects on galaxies and galaxy clusters, astronomers hope to better understand its influence and its true nature. “Euclid will try to find answers to the cosmological questions from ESA’s Cosmic Vision program, and it is fantastic that he is moving into the next phase of development – today we are one step closer to understanding the darkest secrets of the universe,” explains René Laureijs. , Euclides project scientist for ESA.