× close
Euclid’s strength lies in its diversity: this small section of Euclid’s large image map shows a detail of the Perseus galaxy cluster. The different types and shapes of galaxies forming part of the cluster in the foreground at a distance of 240 million light years and a series of faint, diffuse spots in the background are clearly recognizable – galaxies whose light traveled for billions of years ago. Euclid imagined it. Credit: ESA/Euclid/Euclid Consortium/NASA, Image processing by J.-C. Cuillandre, G. Anselmi; CC BY-SA 3.0 IGO
Two things are necessary to understand how the universe came into existence and how it evolved to its current form. Cosmological computer models use the laws of physics to describe the expected appearance of the universe today, while observations made with telescopes test whether these models are correct.
The Euclid Space Telescope, for the first time, will have the capacity to measure the position of billions of galaxies in three dimensions, covering almost the entire universe observable from Earth. The first scientific images have been published.
Euclid, the European Space Agency’s (ESA) latest space telescope, has released its first color images from space. These images result from the combination of data from its two instruments: VIS (Visible Instrument) and NISP (Near-Infrared Spectrograph and Photometer), designed to capture visible and near-infrared light using large area detectors. Euclid’s most important task is to make the most detailed three-dimensional map of the universe, thereby revealing some of its dark secrets.
German members of the Euclid consortium, including the Max Planck Institutes for Astronomy and Extraterrestrial Physics, developed key technical components of the telescope. They also provide logistical services to manage the immense data flows and ensure the quality of the published data.
Previous space telescopes, such as Hubble or James Webb, were built to examine very small areas of the sky in great detail. Euclid, for its part, expands the view with equally high image quality: thanks to its large optics, sensitive instruments and its position outside the disruptive atmosphere of the Earth, it provides images of large parts of the sky in a relatively short observation time, which are also remarkably sharp and contain the faint light of distant galaxies.
With the published images, members of the Euclid consortium demonstrate the full potential of Euclid using five selected objects. Each image covers an area slightly larger than the full moon. At the end of the mission, around 40,000 such image sections will be merged, forming a large area of around 14,000 square degrees in the sky. This constitutes a third of the entire sky, excluding our own galaxy, the Milky Way.
The newly released images make one thing very clear: each image will be a treasure trove of new knowledge about the physics of individual stars, the Milky Way or distant galaxies.
“The telescope will collect enormous amounts of data and detect more objects than before,” says Maximilian Fabricius of the Max Planck Institute for Extraterrestrial Physics in Garching near Munich and the Ludwig Maximilian University in Munich. Knud Jahnke, instrument researcher at the Max Planck Institute for Astronomy in Heidelberg, agrees: “We all have to adapt to the wealth of information that Euclid will provide us. »
An example is the Perseus galaxy cluster. These galaxy clusters are among the largest and most massive structures in the universe. Without dark matter networks, the galaxies shown here would be evenly distributed across the sky. “Thanks to Euclid’s immense field of view and exceptional sensitivity, the galaxies in the Perseus Cluster can be measured down to their farthest and faintest regions,” explains Matthias Kluge, a scientist at the Perseus Cluster. Max Planck Institute for Extraterrestrial Physics and Ludwig-Maximilians. -University.
“There are also other galaxies in the same image that are not connected to the Perseus cluster. The farther out in the universe you look, the more ancient galaxies you will find, given the finite speed at which light moves, and the more galaxies you find.”
About 95% of our universe appears to be made up of mysterious “dark” elements, which also play a role in the formation of the Perseus galaxy cluster. While dark matter determines the gravitational effect between and within galaxies and initially slows the expansion of the universe, dark energy is behind the current accelerated expansion of the cosmos. However, the nature of dark matter and dark energy remains elusive.
What scientists do know is that these substances cause subtle changes in the appearance and movements of objects observed through telescopes. To detect the “dark” influence on the visible universe, Euclid will observe the shapes, distances and movements of billions of galaxies up to 10 billion light years away over the next six years.
Here, spectral information from the NISP infrared instrument is complemented by optical spectra from ground-based telescopes, which will very precisely determine the distances and movements of galaxies imaged by Euclid and translate Euclid’s two-dimensional photos into the most accurate three-dimensional images. complete. map of the visible universe ever created.