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Quick factsWhat it is: RAD-Bow-And-Arrow Radio GalaxyWhere it is: 2 billion light-years from EarthWhen it was shared: June 22, 2026The universe is full of structures that remind us of Earthly objects, such as the Cat's Eye Nebula, a "cosmic hamburger," and the famous Crab Nebula. Now, one more has been added to the list: a radio galaxy shaped like a bow and arrow. The newly discovered galaxy, dubbed the RAD-Bow-And-Arrow Radio Galaxy (RAD-BAARG), sits roughly 2 billion light-years from Earth.Radio galaxies are powered by actively feeding supermassive black holes that launch powerful jets of charged particles in opposite directions. As these high-speed jets crash into the surrounding medium, they form huge lobes of magnetized plasma that can stretch for thousands to millions of light-years. Inside both the jets and the lobes, electrons spiral around magnetic-field lines and emit radiation that is detected at radio wavelengths. As a result, most radio galaxies look roughly symmetrical, like two matching balloon-like radio lobes inflated on each side of the central galaxy. RAD-BAARG, with its lopsided structure, appears to be an oddball.RAD-BAARG was first spotted by citizen scientist Pranim Limbo while inspecting ultrasensitive radio images from the LOFAR Two-metre Sky Survey. Limbo made the discovery through India's RAD@home Astronomy Collaboratory, a citizen-science research initiative in India, in collaboration with an international team of researchers. The new image shows RAD-BAARG in stunning detail, with red tracing the radio emission captured by the LOFAR telescope, combined with an optical image from the Beijing-Arizona Sky Survey.Researchers think the strange shape may have been influenced by the galaxy's environment. RAD-BAARG appears to be falling toward a nearby cluster of galaxies, plunging through the intracluster medium, ‪the hot, thin gas that fills the space between galaxies, the researchers explained in a paper published June 22 in the journal Monthly Notices of the Royal Astronomical Society."The structure of this source is unlike that of any radio galaxy I have seen in the last 25 years," Ananda Hota, principal investigator of the RAD@home Astronomy Collaboratory and first author of the paper, said in a statement. When a galaxy moves through this gas faster than the speed of sound within it, it creates a shock front, similar to how a fighter jet generates a sonic boom. This compressed wall of gas piles up ahead of the galaxy as the gas falls inward.One of RAD-BAARG's jets appears to be running straight into this shock front, causing it to bend and compress into the shape of a drawn bow. The enormous bow-like structure extends nearly 1.8 million light-years across. On the opposite side, the other jet doesn't face the same resistance. Instead, it twists into a distorted S shape before fading into a faint tail forming the "arrow." According to the study, RAD-BAARG has a length of about 2.3 million light-years. That places it in the category of "Giant Radio Galaxies," which are some of the largest standalone single structures in the universe.Astronomers have long predicted that infalling galaxies should generate bow shocks as they plunge through the hot gas of a galaxy cluster. But actually catching one has been extremely difficult, since the surrounding gas is too diffuse and faint to detect easily. Sitting in a complex, chaotic environment, RAD-BAARG is rare not only for its unique shape but also for providing a direct, detailed view of this elusive phenomenon. In other words: That’s a bullseye.See more space photos of the week: 'Human minds should not go through this' The Artemis II crew recalls the unreal moment when Earth disappeared Hidden structure in 1st Vera Rubin image First-light images from the Vera C. Rubin Observatory reveal a 163,000-light-year stream of stars emanating from a nearby galaxy. JWST peeps the 'Eye of God' A spectacular James Webb telescope image reveals intricate structures inside the Helix Nebula.

UK is latest country to set minimum age for social media access but big tech is fighting back globally against curbsSocial media bans go global: big tech faces a reckoning after Australia’s crackdownArturo Béjar, a former employee turned whistleblower at Mark Zuckerberg’s Meta, has talked to parents around the world. He says they share the same perspective: they dread the day their children are old enough to go online.Governments appear to be listening too. This month the UK became the latest country to state that it would set a minimum age of 16 for accessing major social media platforms. Social media bans are becoming a legislative trend after the precedent set by Australia last year, when it imposed an age limit on platforms including Meta’s Instagram and Facebook, Google’s YouTube, Elon Musk’s X, TikTok and Snapchat. Continue reading...

If you push two metal plates together on Earth, nothing happens. But if you take those same plates into the vacuum of space, they can fuse into a single piece of metal. This phenomenon, called cold welding, has been a known hazard for spacecraft engineers for a long time. So what's actually happening at the atomic level, and why does space make it so much easier?The answer comes down to a lack of oxygen in space, experts told Live Science.Sign up for our newsletter(Image credit: Marilyn Perkins / Future)Sign up for our weekly Life's Little Mysteries newsletter to get the latest mysteries before they appear online.Metals are made of lattices — structures where atoms are bonded to one another. But atoms near the surface of a metal aren't bonded to anything on the outward-facing side. If given the chance, they'll "reach out" and share electrons with the surface of another piece of metal. But on Earth, nearly every metal surface is coated in an oxide layer. The layer is just a few atoms thick and forms when metal meets oxygen. "Once the oxide is formed, it's over," Julia Greer, a materials scientist at Caltech, told Live Science. "Then it can't cold weld anymore, because the oxygen basically passivates these bonds."That thin oxide acts like an insulating wrapper. Without it, the free electrons at the surface of one metal piece stop recognizing which atom they belong to. "Those electrons don't know if it's in this piece or if it's in that piece, so they begin sharing the electrons, and essentially that cold welds things together," Sven Bilén, a professor of engineering design and aerospace engineering at Penn State, told Live Science.In space, there's no oxygen to rebuild that layer once it's gone. The cold and the radiation make things worse. Bombardment from solar and ionic radiation in orbit can scour metal surfaces clean, Greer said, leaving freshly exposed atoms primed to bond. "Everything in space is conducive to cold welding," she said.Metal surfaces are never perfectly smooth, either. At a microscopic level, they're jagged ‪—‬ more like tiny mountain ranges than flat plains, said Zachary Cordero, an aerospace engineer at MIT. Pressing two surfaces together, especially with any sliding or vibration, can shear off the oxide layer that formed while the metal was on Earth and flatten those peaks into metal-to-metal contact. "You're breaking up the surface oxide, and you're forming metallurgical bonds," Cordero said.Why cold welding worried early spacecraft engineersCold welding in space has long been a problem. "If there is cold welding, things can become stuck in place," Cordero told Live Science. "If you have a deployable structure and there's cold welding, you might freeze the mechanism, or a door might become locked, or something might become immobilized, which you don't want." For example, say you were to add a metal screw to a metal door. After a while, you would not be able to unscrew it because it would have become part of the door.Bilén pointed to NASA's Galileo probe, which launched in 1989: lubricant loss and launch vibrations during launch are thought to have stripped the oxide layer from parts of its furled high-gain antenna. When engineers attempted to deploy the antenna in 1991, it never fully opened. An illustration of NASA's Galileo spacecraft, whose high-gain antenna never fully deployed during its journey to Jupiter. The failure is widely attributed to cold welding. (Image credit: MARK GARLICK/SCIENCE PHOTO LIBRARY via Getty Images)Some metals are more troublesome than others. Gold and platinum don't form an oxide layer at all, even on Earth, which makes them notoriously prone to cold welding. "Gold definitely is a very notorious metal for cold welding," Greer said, adding that gold's softness lets it conform easily to whatever surface it touches and it bonds even more easily.How to prevent cold welding in spaceTo prevent components from accidentally fusing in orbit, engineers rely on a few strategies. One is anodizing, a process that locks an artificial oxide layer onto a metal surface. Another method is to coat moving parts with dry lubricants, such as molybdenum disulfide, to physically keep surfaces from touching.Related mysteriesCan other metals be turned into gold? Why doesn't stainless steel rust?How do tiny pieces of space junk cause incredible damage?A third strategy is to pair dissimilar metals — for instance, gold next to a "body-centered" metal, like molybdenum — so their atomic structures don't mesh as neatly. "Their packing order is not quite perfectly aligned, and so there'll be a lot more energetic kind of barrier to overcome," Greer said. Before launch, hardware also gets shaken on vibration tables and cycled through extreme hot-and-cold swings inside vacuum chambers, simulating the stresses of liftoff and orbit to catch problems on the ground.Even with all of those precautions, cold welding can still happen. Bilén recalled bolts in his own lab's vacuum chamber fusing shut after a move across campus. They eventually had to be drilled out. "It happens even on Earth," he said.See how much you know about human exploration into space with our spaceflight quiz!