Astronomers discover dark matter 'bridge' linking colliding galaxies: 'This is the missing piece we've been looking for.'
Astronomers have discovered a long-missing element of a galactic collision involving the Perseus galaxy cluster, located 240 million light-years from Earth. This element, a newly detected "subcluster," is 1.4 million light-years to the west of NGC 1275, the central galaxy of the Perseus cluster. These two elements seem to be connected by a faint "bridge" of material.
The structural backbone of this bridge is dark matter, the universe's most mysterious "stuff." Dark matter remains effectively invisible by not interacting with light, but its interaction with gravity has helped to shape galactic structures.
"This is the missing piece we've been looking for," team member James Jee said in a statement. "All the odd shapes and swirling gas observed in the Perseus cluster now make sense within the context of a major merger."Galaxy clusters are some of the largest structures in the known universe, consisting of thousands of galaxies bound together by gravity.
Scientists have long believed that these clusters grow through high-energy mergers that may well be some of the most powerful events in the cosmos since the Big Bang.With a mass equal to around 600 trillion suns the Perseus cluster has long been considered to be the "poster child" for galaxy clusters. However, this model galaxy cluster has been lacking is the telltale signatures that point toward its growth via merger.That was, until now.
To tackle this mystery, Jee and colleagues used the Subaru Telescope and its Hyper Suprime-Cam to probe deeper into the Perseus than ever before.
This investigation hinged on a phenomenon called "gravitational lensing," first predicted by Albert Einstein in his 1915 magnum opus theory of gravity known as "general relativity."
General relativity states that objects with mass cause the very fabric of spacetime (the 4D unification of space and time) to warp, with gravity arising from this curvature.
When light from a background object passes through spacetime warped by a massive body, like a cluster of galaxies, its path is curved. This can cause the light to be amplified, thus magnifying that background body, hence the term "lensing."This effect can also reveal things about the lensing body, including its structure. And because dark matter has mass and therefore warps space and diverts light through its gravitational influence, lensing can also reveal the distribution of a gravitational lens' dark matter content.
In this case, that process revealed the presence of a massive "clump" of dark matter in the Perseus cluster weighing in at 200 trillion solar masses. This clump is linked to the core of the Perseus cluster by a much lighter but significant dark matter bridge.
The team performed simulations of the Perseus cluster, which revealed that this clump collided with the cluster around 5 billion years ago. What remains of this cluster is still sculpting the Perseus cluster today.
Related Stories:
— Did dark matter help black holes grow to monster sizes in the infant cosmos?
— What is dark matter made of? New study bolsters case for 'primordial' black holes
— Supermassive black holes in 'little red dot' galaxies are 1,000 times larger than they should be, and astronomers don't know why
"This breakthrough was made possible by combining deep imaging data from the Subaru Telescope with advanced gravitational lensing techniques we developed — demonstrating the power of lensing to unveil the hidden dynamics of the universe's most massive structures," Jee concluded.
The team's research was published on Wednesday (April 16) in the journal Nature Astronomy.

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
7 hours ago
- Yahoo
An enormous 'X' and 'V' will grace the moon's surface on July 2. Here's how to see them
When you buy through links on our articles, Future and its syndication partners may earn a commission. The nights surrounding the first quarter moon phase on July 2 present a good opportunity to spot colossal 'X' and 'V' features emblazoned on the lunar surface. This month's first quarter phase occurs at 11:41 p.m. EDT on July 2 (0341 GMT on July 3), at which time the right side of the half-lit lunar disk will be illuminated by direct sunlight from the perspective of viewers in the northern hemisphere on Earth. At this time, the sun shines at such an angle to make it appear as if there is a gigantic 'V' and 'X' marking the barren lunar surface. This kind of phenomenon is referred to as a 'clair-obscur' effect and occurs when the interplay between light and shadow leads to the chance formation of familiar shapes on the moon's craggy terrain. The lunar letters are visible for roughly four hours in the run-up to each first quarter moon phase and are at their most impressive when seen just on the 'night' side of the terminator, with their upper reaches kissed by the sun's light. Try and find the lunar 'X' and 'V' on the lunar disk at sunset on July 2 and be sure to keep checking back to see how these shapes evolve over time. If you miss the letters on the night side of the terminator, there's no need to lose hope, as they'll continue to be visible for a brief period after they pass to the 'day side' of the moon. The lunar X is an optical effect formed when sunlight strikes elevated rim sections of the Bianchini, Purbach and La Caille Craters around the first quarter moon phase, according to stargazing website The feature can be found around 25 degrees south of the lunar equator close to the terminator, which is the line separating the dayside and nightside of the moon, close to the prominent Werner and Aliacensis Craters. To find the lunar 'V', moongazers must follow the line of the terminator up to a point less than 10 degrees above the lunar equator to find the partially shadowed form of the Ukert Crater. Both objects can be spotted through a small backyard telescope with a 6-inch aperture, though a larger scope will help resolve detail in the myriad craters and broken terrain dotting the surrounding moonscapes. TOP TELESCOPE PICK Want to see the lunar X and V? The Celestron NexStar 4SE is ideal for beginners wanting quality, reliable and quick views of celestial objects. For a more in-depth look at our Celestron NexStar 4SE review. Stargazers interested in exploring the lunar surface should check out our guides to the best telescopes and binoculars available in 2025. Photographers interested in capturing the moon's surface should also read our roundup of the best cameras and lenses for astrophotography. This article was updated at 3:10 a.m. EDT (0810 GMT) on July 2 to change 'June 2' to the correct date of 'July 2'. Editor's Note: If you capture a picture of the letters on the moon and want to share it with readers, then please send your photo(s), comments, and your name and location to spacephotos@
Yahoo
14 hours ago
- Yahoo
Space calendar 2025: Rocket launches, skywatching events, missions & more!
When you buy through links on our articles, Future and its syndication partners may earn a commission. 2025 is a busy year for spaceflight and exploration with countless launches, mission milestones, industry conventions and skywatching events to look forward to. With so much going on, it's hard to keep track of everything. Never fear — keep up with the latest events in our 2025 space calendar. You can also Find out what's up in the night sky this month with our visible planets guide and skywatching forecast. Please note: Launch dates are subject to change and will be updated throughout the year as firmer dates arise. Please DO NOT schedule travel based on a date you see here. Launch dates are collected from NASA events, ESA news, Roscosmos space launch schedule, Spaceflight Now launch schedule, Everyday Astronaut, Supercluster and others. Related: Wondering what happened today in space history? Check out our "On This Day in Space" video! Is there a rocket launch today?
Yahoo
18 hours ago
- Yahoo
Astonishing 'halo' of high-energy particles around giant galaxy cluster is a glimpse into the early universe
When you buy through links on our articles, Future and its syndication partners may earn a commission. A vast cloud of energetic particles surrounding a cluster of galaxies that existed around four billion years after the Big Bang could help scientists discover how the early universe took shape. But was the halo of the massive cluster of galaxies — called SpARCS104922.6+564032.5, and located 9.9 billion light-years from Earth— built by erupting supermassive black holes or a cosmic particle accelerator? This envelope of radio-emitting particles — a so-called "radio mini-halo," though it isn't really mini at all — is the most distant example of such a structure ever detected. Its distance is double that of the next farthest radio mini-halo, with its radio signal having taken 10 billion years to reach Earth — the majority of the universe's 13.8 billion-year lifespan. The discovery, made with the LOFAR (LOw Frequency ARray) radio instrument in Europe, indicates that galaxy clusters, which are some of the largest structures in the known universe, spend most of their existence wrapped in envelopes of high-energy particles. This insight gives scientists a better idea of how energy flows around galaxy clusters. And that in turn could improve our picture of cosmic evolution, study members said. "It's astonishing to find such a strong radio signal at this distance," study co-leader Roland Timmerman, an astronomer at Durham University in England, said in a statement. "It means these energetic particles and the processes creating them have been shaping galaxy clusters for nearly the entire history of the universe." The team posited two possible explanations for the formation of this mini-halo. One possibility is that the supermassive black holes at the hearts of the galaxies in the cluster are ejecting jets of high-energy particles and settling around their home cluster. One problem with this theory, however, is explaining how these particles have managed to maintain their energy as they take their place in a gigantic cloud. The second possible explanation is the existence of a natural particle collider around the galactic cluster. Particles in the hot ionized gas, or plasma, around the cluster may be slamming together at near light-speeds, resulting in the highly energetic particles in the halo. Related Stories: — This baby galaxy cluster is powering extreme star formation with a hidden fuel tank — Our expanding universe: Age, history & other facts — World's largest visible light telescope spies a galaxy cluster warping space-time The team behind the new research believes their results offer a rare chance to observe a galaxy cluster just after it has formed. It also suggests that galactic clusters are filled with energetic particles for billions of years longer than had previously been thought. And further study of this distant radio mini-halo should reveal just where these charged particles originated, according to the scientists. The team's research has been accepted for publication in the Astrophysical Journal Letters, with a preprint version available on the research repository arXiv.