Researchers in Innsbruck find dwarf galaxies – tirol.ORF.at

The discovery is part of the first scientific findings from ESA's space telescope, which have been documented in ten publications on the arXiv preprint server.

16 million objects in 24 hours

Euclid's first phase data covers 17 astronomical features, from nearby gas and dust clouds to distant galaxy clusters. In just 24 hours, more than eleven million objects were recorded in visible light and another five million in infrared light – for ESA, “a small glimpse of what Euclid can achieve.”

The first results demonstrate Euclid's strengths: “The new instrument can observe a large area of ​​the starry sky at once, thus providing a representative sample of all galaxies,” says Leila Linke from the Institute for Particle and Astrophysics. Physics at the University of Innsbruck in a radio statement. Due to the high sensitivity to surface brightness, dwarf galaxies and very diffuse galaxies can also be found.

The Euclid Space Telescope opens up new worlds

This has been achieved, for example, in the case of the Perseus cluster of galaxies, “a relatively nearby and very massive galaxy cluster at a distance of about 240 million light-years,” Linke explained to the APA. A team led by Francine Marlowe from the University of Innsbruck not only identified 1,100 dwarf galaxies in the cluster that were difficult to find due to their low luminosity, but they also analyzed their structure and size and were able to determine the luminosity function, which indicates how many galaxies with a certain luminosity exist. There gives.

According to Lenke, such dwarf galaxies, which contain between 1,000 and 1 billion stars, are much smaller than the Milky Way, which contains at least 100 billion stars, and do not have the disc or spiral shape known in our home galaxy. The so-called star clusters are even smaller: about 5,000 previously unknown star clusters have been discovered in the Fornax galaxy group in the first images taken by the space telescope. Previously unknown galaxies in the “closest” neighborhood of Earth were also found in the images, where “closest” for astronomers means they are between 1.6 million and 29.7 million light-years away.

Dark and mysterious matter

Galaxy clusters are structures of gigantic proportions: they consist of thousands of galaxies bound together by gravity and also contain a lot of dark matter. This mysterious matter, which makes up 27% of the universe's total energy and matter budget, is invisible but only reveals itself through gravitational effects. Its mass not only affects the motion of stars and galaxies in the cluster, but also distorts light from distant background galaxies.

Tim Schrbach of the Institute for Astrophysics and Particle Physics at the University of Innsbruck and an international team observed the so-called gravitational lensing effect in the Abell 2390 galaxy cluster. “Our study shows how well the new tool is suitable for this analysis.” Shrabak says. “By distorting the shapes of background galaxies, we were able to measure the distribution of dark matter in and around the galaxy cluster.”

A 3D map of the universe will be created

The Euclid Space Telescope, with a diameter of 1.2 metres, is expected to observe billions of galaxies over the next few years, creating the largest and most accurate 3D map of the universe. The nearly 2,000 scientists from 15 countries evaluating mission data hope to use the instrument to obtain more clues about how the universe expanded after the Big Bang, how structures in the universe evolved and what lies beyond previously unexplored dark and dark matter. The energy is there.

According to the European Space Agency, the images taken by Euclid are at least four times clearer than those taken by ground telescopes. The space telescope can “cover wide areas of the sky with remarkable detail and depth and capture a variety of different objects in a single image – from faint to bright, from distant to nearby, and from the most massive galaxy clusters to small planets,” the space telescope said. European Space – Scientific Director Carol Mundell.