The European Space Agency's Euclid spacecraft has released 5 dazzling new images of the cosmos including a colourful star-forming region, enormous galactic clusters and one of the largest known spiral galaxies beyond our cosmic neighbourhood.
Euclid's first scientific data has just been made public, and the brand new images are part of the mission's Early Release Observations.
Euclid mission goals
The Euclid mission is tasked with studying the mysterious phenomena known as dark energy and dark matter.
Dark matter is a substance that cannot be directly detected, but which is thought to make up about 25% of the entire Universe; dark energy is the name given to the unknown force causing the expansion of the Universe to speed up.
Euclid's mission will see it study the web-like structures of the Universe, map billions of galaxies and explore how the Universe formed and evolved over time.
It will do this by observing two billion galaxies to create a 3D map of the universe.
These new images are at least four times sharper than what can be captured using ground-based telescopes, and provide astronomers with new views of the distant cosmos in visible and infrared light.
The images accompany the mission’s first scientific data and 10 forthcoming science papers, and follow the release of Euclid's first colour images in November 2023.
New Euclid science papers include one by Professor Mark Cropper from UCL Mullard Space Science Laboratory in the UK.
Prof Cropper led design and development of Euclid's VIS optical camera, which is one of the largest ever sent into space and was supported by £20 million of UK Space Agency funding.
Let's take a look at each of the images in turn.
Messier 78
Messier 78 will be well-known to astronomers and astrophotographers who've spent time exploring the constellation Orion.
It's a star-forming region 1,300 lightyears from Earth that can be found within Orion.
Euclid's infrared view enables it to peer deep into M78 because it can see through the blanket of interstellar dust that would normally obscure views in visible light.
Euclid has exposed hidden regions of star formation for the first time, mapping M78's filaments of gas and dust: the ingredients out of which new stars will be born.
It's seen star formation in action, too, uncovering newborn stars and planets and detecting objects just a few times the mass of Jupiter.
Euclid's infrared instruments – the VIS and NISP cameras – have uncovered over 300,000 newly-seen objects in this field of view.
Astronomers will use the data to study the number of stars and sub-stellar objects and learn more about how stars form and evolve.
Could sub-stellar objects like brown dwarfs and rogue planets be candidates for dark matter?
Data on these objects from the Euclid observations will help astronomers get closer to answering this question.
Abell 2390
Abell 2390 is a galaxy cluster, a huge grouping of galaxies held together by gravity, 7 billion lightyears away in the constellation of Pegasus.
Consider just how huge a galaxy is, then consider that Abell 2390 contains over 50,000 of them all grouped together.
Euclid observations will enable astronomers to measure distances to these galaxies.
Galaxy clusters like this can collectively contain mass up to 10 trillion times that of the Sun.
Much of this is in the form of dark matter, which can't be directly detected, but its presence can be inferred through its gravitational interactions with visible matter.
Euclid used a technique called gravitational lensing to probe the undetectable matter in Abell 2390.
This is a technique that was predicted by Einstein and involves the warping of spacetime by matter.
In the case of a galaxy cluster, light from more distant galaxies is bent and warped by the mass of the cluster, and appears as giant curved arcs in this image.
Some of these arcs are even multiple views of the same object, such is the distortion of light caused by gravitational lensing.
This information helps astronomers learn more about the distribution of dark matter, how galaxy clusters change over time, and the evolution of the Universe.
NGC 6744
NGC 6744 is a spiral galaxy 30 million lightyears away within the Local Group, which is a group of galaxies containing our own Milky Way galaxy.
Galaxy NGC 6744 is one of the largest spiral galaxies beyond our local patch of space and is an active star-forming galaxy.
Euclid’s wide field of view means it's been able to capture the entire galaxy and surrounding area, revealing the galaxy's spiral structure and lanes of dust.
The Euclid observations will enable astronomers to count individual stars within the galaxy and trace the distribution of stars and dust.
Cosmic dust and gas fuel star formation, and so these observations provide insight into how stars form and how that star formation affects galaxy evolution.
This could help answer some fundamental questions surrounding why our Universe looks the way it does today.
The dataset will help astronomers learn more about the role played by dust and gas in the formation of stars and how populations of stars are distributed throughout galxies.
It will also provide information on the role that spiral structures play in star formation and why galaxies look and behave the way they do.
And Euclid has already found a new dwarf satellite galaxy of NGC 6744, showing even more discoveries could be on the way.
Abell 2764 (and bright star)
Galaxy cluster Abell 2764 can be seen in the top right of this Euclid image.
It's a cluster containing hundreds of galaxies within a halo of dark matter, 1 billion lightyears away in the direction of the Phoenix constellation.
Euclid's view shows background galaxies, distant galaxy clusters and interacting galaxies.
It's allowing astronomers to measure the radius of the galaxy cluster and its outskirts.
Theses observations, and those of Abell 2390, allow astronomers to study distant galaxies that existed during the cosmic dark ages.
Because light from these distant galaxies takes billions of years to reach us, when we look deep into space we're looking back in time, seeing the galaxies as they existed when the Universe was just 700 million years old.
The Universe is currently 13.8 billion years old, which means Euclid's observations give astronomers the chance to see what galaxies looked like when the Universe was just 5% of its current age.
Another highlight of the image is the prominent bright star, which is much closer than the galaxy cluster.
In fact, this star is within our own galaxy and is known as V*BP-Phoenicis. It can be seen in the Southern Hemipshere sky.
The spiked shape is an optical effect known as diffraction spikes caused by light passing through the telescope's optics.
Euclid was designed to make this scattering of light as low as possible, enabling more accurate measurements of the star and greater study of galaxies that lie nearby, which are usually drowned out by the star's brightness.
Dorado Group
The Dorado Group is a galaxy group that lies 62 million lightyears away in the southern hemisphere constellation of Dorado.
Euclid has observed tidal tails and shells that are signs of interactions between galaxies, showing how they're evolving and merging over time.
Many of the galaxies within the Dorado group are still forming stars, while others show signs of having formed sttars very recently.
How do galaxies merge and collide, and what happens to the stars gas and dust within colliding galaxies?
Euclid's dataset is helping astronomers get closer to answering these questions, improving models of cosmic history and understanding how galaxies form within haloes of dark matter.
The Euclid spacecraft adopts a combination of large field-of-view and high spatial resolution, enabling the capture of tiny objects, wider views and extended features using the same instrument and observations over a large part of the sky.
And by cataloguing the individual star clusters within the Dorado Group, astronomers can trace how the galaxies formed and study their individual histories.
Science takeaways
"A key part of our purpose as a space agency is to understand more about the Universe, what it’s made of and how it works," says Dr Caroline Harper, Head of Space Science at the UK Space Agency.
"There is no better example of this than the Euclid mission - we know that most of Universe is made up of invisible dark matter and dark energy, but we don’t really understand what it is, or how it affects the way the universe is evolving.
"Science missions like Euclid generate vast quantities of valuable data for scientists across the world, and UK researchers have played a leading role in the development of the mission and in delivering these early results, less than a year after launch."
"Euclid is a unique, ground-breaking mission, and these are the first datasets to be made public – it’s an important milestone," says Valeria Pettorino, ESA’s Euclid Project Scientist.
"The images and associated science findings are impressively diverse in terms of the objects and distances observed. They include a variety of science applications, and yet represent a mere 24 hours of observations. They give just a hint of what Euclid can do. We are looking forward to six more years of data to come!"
"It’s no exaggeration to say that the results we’re seeing from Euclid are unprecedented," says ESA Director of Science, Prof. Carole Mundell.
"Euclid’s first images, published in November, clearly illustrated the telescope’s vast potential to explore the dark Universe, and this second batch is no different.
"The beauty of Euclid is that it covers large regions of the sky in great detail and depth, and can capture a wide range of different objects all in the same image – from faint to bright, from distant to nearby, from the most massive of galaxy clusters to small planets. We get both a very detailed and very wide view all at once. This amazing versatility has resulted in numerous new science results that, when combined with the results from Euclid’s surveying over the coming years, will significantly alter our understanding of the Universe."
