Editor’s note: The new Euclid telescope images were released at 5:00 a.m. EDT (1200 CEST). You can see five new views of the universe here in our picture release story.
The European Space Agency (ESA) will release five new images from the Euclid Space Telescope today (May 23). And as for the previous set of images, space fans should be in for an absolute treat.
“During the initial phase of the Euclid observations, five new portraits of our universe were captured, each revealing amazing new science,” ESA officials said in a statement. “Euclid’s ability to unlock the secrets of the universe is something you won’t want to miss.”
The new images will be revealed at 5:00 a.m. EDT (1200 CEST) and are accompanied by an incredible 10 scientific papers. You can watch the data release live on ESA’s YouTube channel.
Related: The Euclidean “dark space” telescope is de-iced from a million miles away
As an appetizer for the occasion, perhaps we can recall the incredible cosmic images this mission has provided so far.
Euclid’s story so far
Euclid, which launched from Cape Canaveral, Florida on July 1, 2023 atop a SpaceX Falcon 9 rocket, Euclid is a wide-field space telescope with a 600-megapixel camera that observes the universe in visible light, a near-infrared spectrometer, and a photometer used to determine the redshift of galaxies . Knowing the redshift allows scientists to determine how fast distant galaxies are moving away from our planet.
Euclid’s main task is to investigate the two most mysterious elements of the universe: dark energy and dark matter. Together, these phenomena make up what is often called the “dark universe”.
Dark energy is a placeholder name for any force that causes the expansion of the universe to accelerate. Dark matter, on the other hand, is a form of matter that is effectively invisible because it does not interact with light. This means that scientists know that it is not the “ordinary” matter made up of electrons, protons and neutrons that includes stars, planets, moons and our bodies. Dark matter can only make its presence known through its interactions with gravity, which in turn can affect ordinary matter and light. However, to be clear, neither dark matter nor dark energy are necessarily made up of the same thing. Both may be made of many things – or perhaps they are indeed each made of one homogeneous thing.
The thing is, we just don’t know.
However, dark energy is thought to make up about 68% of the energy and matter budget of the universe, while dark matter makes up about 27%. This means that the dark universe makes up 95% of the stuff in the universe, and the stuff we can actually understand makes up only about 5%.
Euclid, nicknamed the “dark space detective” thanks to its specific toolkit, clearly has its work cut out for it. But sure enough, the first official images from the space telescope released on November 7, 2023, after its first four months in space, showed that it had accomplished the task.
Right above is one of the first images the public saw from the Euclid telescope. It’s an image showing about 1,000 galaxies, all belonging to the Perseus cluster. Located about 240 million light-years from Earth, this cluster is one of the largest structures in the known universe.
Mapping galaxies in such vast volumes is key to understanding how dark matter is distributed and how this distribution has affected the evolution of the universe.
In addition to the wealth of galaxies in the Perseus cluster, the image also showed another 100,000 much more distant galaxies, each containing up to hundreds of billions of stars. Observations of distant galaxies in large numbers like this one are the key to Euclid revealing how dark energy pushes these galaxies out faster and faster by accelerating the expansion of the space between them.
Just because Euclid has his eyes on vast swathes of galaxies doesn’t mean he can’t impress images of individual galaxies.
Another of the first Euclidean images we were able to look at was somewhat ironic for an instrument tasked with revealing the dark elements of the universe. That’s because he identified the galaxy IC 342, also known as the “Hidden Galaxy”.
Located about 11 million light-years from Earth, this galaxy is difficult to image because it lies behind the bright, dusty disk of the Milky Way. However, this did not stop Euclid from taking an incredible picture of this once hidden spiral galaxy. The space telescope used its near-infrared instrument to do this, which is advantageous because the gas and dust of the Milky Way’s disk are less efficient at absorbing infrared light compared to other wavelengths of electromagnetic radiation.
To unravel the mysteries of the dark universe and create a detailed 3D map of the universe, Euclid will need to image galaxies up to 10 billion light-years away by seeing a universe that is 13.8 billion years old, since it was less than 4 billion years after the big bang.
These galaxies are unlikely to have the neat, spiral arrangement of the Milky Way or even the Hidden Galaxy. Most galaxies in the early universe are “blobby”, poorly shaped, irregular galaxies that served as building blocks for larger galaxies.
To prepare for observing these distant and early galaxies, Euclid’s first images included a look at the more local irregular galaxy NGC 6822, located just 1.6 million light-years from Earth.
Although they offer us spectacularly sparkling images, Euclid will not only focus on galaxies during its mission.
As the image of NGC 6397 above shows, the space telescope will also be observing globular clusters. And luckily, globular clusters are just as beautiful. They are conglomerates of hundreds of thousands of stars bound together by gravity and are some of the oldest structures in the known universe.
NGC 6397 is the second closest globular cluster to Earth at a distance of only 7800 light years. Globular clusters like NGC 6397 orbit the Milky Way’s disk and may hold clues to the evolution of either our galaxy or at least other galaxies that host such structures.
Euclid will excel at studying globular clusters because, unlike other telescopes, it has a wide enough field of view to capture entire globular clusters in one image, as it did for NGC 6397.
Much of the Euclid mission will focus on the unknown, but the final image from the first batch of Euclid releases actually showed us a familiar celestial object in a whole new light. A dark space detective has been able to create an amazingly detailed panoramic view of the Horsehead Nebula, also known as Barnard 33.
Located about 1,380 light-years from Earth and located close to the east of Orion’s belt, the Horsehead Nebula is one of the closest star-forming clouds of gas and dust to the Solar System. It’s quite a sight to see, too.
Although many telescopes have imaged the Horsehead Nebula in the past, none have captured this region of the molecular cloud in Orion with such a wide and sharp view. What’s even more amazing about this picture is that it only took Euclid an hour of observation to create it. It’s no wonder professional and amateur astronomers and space enthusiasts are excited about the upcoming May 23 data release.
To that end, as stunning as the images above are, there’s a good chance the best is yet to come from Euclid as it begins to fulfill its mission objectives and shed strange light on the dark universe.
We’ll have to wait until Thursday to see what the next crop of Euclid images will bring, and see how this dark space sleuth begins to live up to his expectations for a huge mission after nearly a year in space. But then again, if his past is any indication of his future, it’s hard to imagine anything but information-rich beauty from these images.