The European Space Agency (ESA)’s Euclid space telescope has sent back its first scientific images, and they are absolutely stunning. Each of the five images of the glowing cosmic objects will eventually be part of Euclid’s 3D map of the universe, the ultimate goal of which is to understand the dark components of our universe.
Euclid launched on July 1 and now stands about 1.5 million kilometers from Earth. Over the next six years, it is expected to image about one-third of the sky, creating the most detailed 3D map of the universe ever made. This map will give researchers an unprecedented window into the large-scale structure of the universe, helping them understand the behavior of dark matter and dark energy on the cosmic scale and how it may deviate from our current understanding of physics and cosmology.
Dark matter and dark energy are invisible, hence the nickname “dark”, so the only way to detect their behavior is through images of visible objects, like the one Euclid has now released. The first of these images shows the Horsehead Nebula, located in the Orion constellation 1375 light years from Earth. This nebula is well known, but the incredible detail in this new image could allow scientists to see new stars and even young planets.
This is a sparkling cluster of hundreds of thousands of stars A globular cluster called NGC 6397. The sheer scale of these clusters means that it is difficult to capture them in detail without many observations, but Euclid’s large field of view makes this possible. Researchers aren’t sure whether globular clusters are underlying dark matter haloes, a question that may be answered by Euclid’s measurements.
Each of the above pictures shows a galaxy. On the left is the spiral galaxy IC 342, nicknamed the Hidden Galaxy because it is located on the other side of the Milky Way disk from Earth, making it difficult to observe through all the stars, gas, and dust. This galaxy contains many globular clusters and is very similar to our own Galaxy, making it an excellent point of comparison to understand whether a galaxy is normal or unusual.
The irregular galaxy at right is NGC 6822, representative of a type of galaxy that was common in the early universe. Many of these smaller galaxies with less obvious structure merged over time and became more massive galaxies such as the Milky Way or the Hidden Galaxy. During its mission, Euclid will observe billions of galaxies, and mark each one’s location in the greater cosmic web.
Although this image may appear to be a single irregular galaxy or globular cluster at first glance, it actually shows over 100,000 galaxies. About 1000 of them, in the foreground of the image, belong to the Perseus galaxy cluster. Many of them have never been seen before. Such massive structures are only possible due to the influence of dark matter, so such observations will be important to ascertain its true nature.