ESA mission to study the "dark side" of the Universe passes important test

In 2020, the European Space Agency (ESA) will launch the Euclid mission, with the ambition of tracking the shapes and positions of 2 billion galaxies, coveringcovering more than a third of the sky. The Euclid mission will enable us to learn about the properties of dark matter and dark energy, and thus better understand the formation and evolution of the Universe. Last week, the first step was taken to make this ambitious mission a reality, with the approval of the so-called Preliminary Design Review (Preliminary Design Review), in which researchers from the Institute of Astrophysics and Space Sciences (IA). With this approval, there is confidence in the capability of the spacecraft and the instruments that will be built, allowing us to move on to the next step—to "cut metal," in the words of the ESA.

The work of the IA team consisted of "delivering a complete observation plan for the six-year duration of the mission, demonstrating that it is indeed possible to scan more than a third of the sky with the quality necessary to achieve the mission's scientific objectives," describes Ismael Tereno, team coordinator. The test demonstrated that the combined performance of the spacecraft, telescope, and instruments will enable the massive amount of data needed to achieve the mission's scientific goals.

 António da Silva, member of the Euclid consortium management team and national coordinator, commented: “This contribution is part of Portugal’s technical responsibilities in the consortium and allows national scientists to participate in the exploration of data from this important mission during its proprietary period.” He added that "The merit of the team's work has been recognized by the consortium, which reflects the excellence and high level of internationalization of science in Portugal in this area."

Portugal joined the Euclid consortium in 2012 through a multilateral agreement signed by FCT, representing Portugal. FCT is a member of the consortium's Steering Committee, which now includes scientists from 14 European countries (Austria, Belgium, Denmark, France, Finland, Germany, Italy, the Netherlands, Norway, Portugal, Romania, Spain, Switzerland, and the United Kingdom) as well as several scientists from the US, including 40 appointed by NASA. The Portuguese participation includes 20 scientists from different institutions, coordinated by the IA.

It is now known that dark matter and dark energy constitute a large part of the matter and energy that exists in the Universe. In fact, normal atoms account for less than 5% of the matter in the Universe. This "dark side" is not, however, visible; its presence is inferred.  Dark matter is inferred from measurements of alignments in the orientations of distant galaxies. Dark energy, on the other hand, explains the speed of the Universe's expansion, as measured by the distribution of galaxies in space.  By enabling the tracking of more than 2 billion galaxies with unique precision, the Euclid mission will allow astronomers to understand the properties and behavior of dark matter and dark energy, as well as to study the mystery of the recent expansion of the Universe.

The mission Euclid was proposed to ESA in 2007, selected as the agency's second medium-class mission in 2011, and formally adopted in 2012 (the year Portugal joined the consortium). The mission is scheduled for launch in December 2020 from the European spaceport in Kourou, French Guiana, aboard a Russian Soyuz rocket. It will orbit at a distance of approximately 1.5 million kilometers from Earth. With the Preliminary Design Review test completed, the next test will take place in two years—the Critical Design Review—after which, if all goes well, the Euclid spacecraft will be assembled.

The four IA researchers, members of the Euclid Sky SurveyWorking Group (ESSWG), are: António da Silva (IA and Faculty of Sciences of the University of Lisbon – FCUL), Ismael Tereno (IA and FCUL), João Dinis (IA and FCUL), and Carla Sofia Carvalho (IA).

Images, from top to bottom:

• The sky covered by the Euclid mission.
• Illustration of the Euclid satellite

(Credits: ESSWG, IA, and ESA)