Launch of the European Euclid mission, at the service of cosmology

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On July 1, a SpaceX launcher sent a new extraordinary European scientific mission to the Lagrange L2 point, dedicated to the study of dark matter and energy.

Revolution in perspective

Cosmologists around the world are currently asking two key questions: what is the nature of dark matter and dark energy and what is the origin of the acceleration of the Universe?

To provide some answers using a large amount of data, the mission Euclid was decided in 2011 as part of the program Cosmic Vision of the’European Space Agency.

It consists of placing Lagrange point L2 of the Earth-Sun system, at a distance of 1.5 million km and a position opposite our star, a telescope which will observe 36% of the sky, and map the general structure of the Universe to more than 10 billion d light years.

It will thus reveal the story of its expansion and the growth of its structure over the last three quarters of its existence, with unprecedented precision.

The volume of data collected promises to be dizzying: 15 Petabytes in the long term.

A revolution in physics in perspective…

Ten years of development

Responsibility for the mission, the development of scientific instruments and the restitution of the data produced were entrusted in 2012 to the Euclid Consortiumpiloted by the Institute of Astrophysics of Paris (DPI).

It now brings together more than 250 research laboratories and more than 2,200 scientists across 17 countries.

In 2013, Thales Alenia Space in Turin, Italy and Airbus Defense and Space in Toulouse were selected, the first as prime contractor, to build the service module and assemble the satellite, and the second to supply the module hosting the Euclid payload.

The spectrograph is produced under the direction of the Laboratoire d’astrophysique de Marseille (AML), and its photometer is equipped with detectors supplied by the Nasa.

The imager is being developed under the guidance of the Space Science Laboratory at Mullard University, UK.

In total, 80 industrialists are associated with the construction of the telescope, including French SMEs Boostec, Reosc, Saft And sodernas well as the Swiss company Beyond Gravity.

The contribution of CNES funds 13 laboratories in the ECA and CNRSand to welcome within the National Institute of Nuclear Physics and Particle Physics (IN2P3), in Villeurbanne, one of ten data reception and archiving centres.

Two month transfer

Euclid was originally scheduled to be launched in mid-2022 from the Guyanausing a Soyuz Russian or a Ariadne 62 (equipped with two booster thrusters).

But the Russian invasion of Ukraine and delays to the new European heavy launcher have brought theESA to turn last November to SpaceX.

The launch of Euclid took place on July 1 at 15:11 UTC, from the military base of Cape Canaveralusing a Falcon 9 equipped with a second-hand floor.

The trip to the Lagrange L2 point should last one month, then two months of acceptance will be necessary before the start of the telescope’s observations.

The first scientific data are expected at the end of the year – obviously with great impatience among astronomers…

John Walker Avatar