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Welcome to the Euclid Science Operations Centre
Euclid is a space-borne survey mission dedicated to investigate the origin of the Universe's accelerating expansion and the nature of dark energy, dark matter and gravity. Euclid will characterise the signatures of dark energy on the 3D distribution of cosmic structures. In 2012, Euclid was approved as the second Medium Class mission (M2) in the Cosmic Vision Programme. Launch is scheduled in July 2023 with a Falcon 9 launcher.
The mission is optimised to measure apparent shapes of galaxies, which are distorted by gravitational deflection of light due to dark matter concentrations, and to measure galaxy clustering, that is the non-random distribution of galaxies in the Universe resulting from the action of gravity. Euclid demands very high precision measurements and the ability to survey the sky at visible and near-infrared (NIR) wavelengths. Such requirements cannot be met from the ground, and calls for a wide-field Visible/NIR space mission. For more information see our SciTech site, and in particular the "red book".
Space Team Europe for Euclid: Henk Hoekstra
Henk Hoekstra, professor of observational cosmology at Leiden University, the Netherlands, shares his professional trajectory linked to weak gravitational lensing, a technique used by ESA's Euclid mission.
Henk explains how Euclid will reveal the dark side of the Universe. He uses enlightening examples involving a swimming pool and other terrestrial objects. Listen to Henk Hoekstra to understand how Euclid can make the invisible visible.
Euclid's view of the Horsehead Nebula
Euclid shows us a spectacularly panoramic and detailed view of the Horsehead Nebula, also known as Barnard 33 and part of the constellation Orion.
At approximately 1375 light-years away, the Horsehead - visible as a dark cloud shaped like a horse's head - is the closest giant star-forming region to Earth. It sits just to the south of star Alnitak, the easternmost of Orion's famous three-star belt, and is part of the vast Orion molecular cloud.
Euclid's view of globular cluster NGC 6397
This sparkly image shows Euclid's view on a globular cluster called NGC 6397. Globular clusters are collections of hundreds of thousands of stars held together by gravity.
Located about 7800 light-years from Earth, NGC 6397 is the second-closest globular cluster to us. Together with other globular clusters it orbits in the disc of the Milky Way, where the majority of stars are located.
Euclid's view of irregular galaxy NGC 6822
To create a 3D map of the Universe, Euclid will observe the light from galaxies out to 10 billion light-years. Most galaxies in the early Universe don't look like a neat spiral but are irregular and small. They are the building blocks for bigger galaxies like our own.
This first irregular dwarf galaxy that Euclid observed is called NGC 6822 and is located close by, just 1.6 million light-years from Earth. It is a member of the same galaxy cluster as the Milky Way (called the Local Group), and was discovered in 1884. In 1925 Edwin Hubble was the first to identify NGC 6822 as a 'remote stellar system' well beyond the Milky Way.
Euclid's view of spiral galaxy IC 342
Over its lifetime, our dark Universe detective will image billions of galaxies, revealing the hidden influence that dark matter and dark energy have on them.
That's why it's fitting that one of the first galaxies that Euclid observed is nicknamed the 'Hidden Galaxy'. This galaxy, also known as IC 342 or Caldwell 5, is difficult to observe because it lies behind the busy disc of our Milky Way, and so dust, gas and stars obscure our view.
Euclid's view of the Perseus cluster of galaxies
This incredible snapshot from Euclid is a revolution for astronomy. The image shows 1000 galaxies belonging to the Perseus Cluster, and more than 100 000 additional galaxies further away in the background, each containing up to hundreds of billions of stars.
Many of these faint galaxies were previously unseen. Some of them are so distant that their light has taken 10 billion years to reach us. By mapping the distribution and shapes of these galaxies, cosmologists will be able to find out more about how dark matter shaped the Universe that we see today.
Preparing for Euclid's first images: from puzzling data to dazzling views
On Tuesday 7 November, ESA will release the first full-colour images captured by its recently launched Euclid space telescope. These images form part of the mission's 'Early Release Observations' – where Euclid was tasked with scrutinising a set of celestial targets chosen for their public appeal and scientific value.
The five images are full of cosmic secrets waiting to be revealed. And this is just the beginning. During its six-year mission, Euclid will generate the equivalent of a million DVDs of data.
In this video, hear from the experts about how Euclid has reached this milestone.