Our Galaxy swallowed another galaxy shortly after the Big Bang. And scientists just found the smoking gun - BBC Sky at Night Magazine

Sound can be a tricksy beast to try to harness. It fills the world around us, bursting from its multitudinous sources, bouncing off surfaces as echoes – a property that makes sound both incredibly useful and deeply vexing, depending on where and how its reverberations occur. There are some circumstances where echoes can cause problems. The most obvious example is sound recording studios, but one major problem area is probably less obvious because it's far more ubiquitous – pipes. Consider ventilation, air conditioning, industrial exhaust, or even plumbing. Sound travels through the spaces enclosed in those pipes and ducts, and when it encounters an obstruction, a change in shape, or a closed end, it can start to rattle around like nobody's business. Now, scientists have developed an ingenious little device that can dramatically reduce those reflections by effectively 'swallowing' sound. It's called a sonic black hole, and the new design can be 3D-printed and inserted directly into an existing pipe – a major step forward from conventional designs that require the black hole to be built into the pipe itself.

There's always a bigger fish in the sea. For most of us, that idiom is a warning – but for one little swimmer in the deep, it's a blessing. The black swallower fish (Chiasmodon niger) is a little creature that grows, on average, just 10-20 centimeters (3.9–7.9 in) long, and no more than a school ruler. Still, that doesn't stop it from aiming high. This unassuming fish can gulp down prey up to ten times its mass. It's an underdog moment for sure – like if David ate Goliath – and in a spectacularly rare event, scientists just captured it on camera. During a recent deep-sea dive near the islands of Trinidad and Tobago, a remotely operated vehicle snapped a black swallower fish at 1,259 meters deep, lugging around a stomach so distended it looks like a sidecar. The skin is stretched almost transparent, to the point where you can actually see its internal organs and intestines. "[Black swallower fish] are notoriously rare to spot in the wild. I saw my first nearly a decade ago in the Gulf of Mexico," says Diva Amon from the Schmidt Ocean Institute, the chief scientist of the expedition. "I never imagined I'd get a second chance. But this expedition delivered BIG.

When we look up at the Sun, we see a star glowing in shades of yellow, orange, and white. Across the universe, stars display a range of colors, from fiery reds to brilliant blues, with their hues shaped primarily by their surface temperatures. But what if the stellar palette extends beyond the colors we’re accustomed to seeing? New findings are bringing some unexpected possibilities into view, suggesting that white dwarfs, the dense remnants of dead stars, could glow in shades of pink, purple, and even green. For the first time, astronomers have spotted a star that appears green to the human eye. The star had reached the end of its lifespan and swallowed up rocky material from its planetary system, giving it a chartreuse green appearance. The findings, published in RAS Technique and Instruments, suggest that planetary debris can cause white dwarf stars to shine in a whole array of colors if viewed up close. Zombie star When a star like the Sun burns through its nuclear fuel, it sheds its outer layers to form a planetary nebula, leaving behind its dense, dead core in the center.

Lawrence Livermore National Laboratory researcher Isaiah Santistevan led the development of three-dimensional simulations exploring how a nuclear device could deflect or disrupt an asteroid threatening Earth. Credit: Blaise Douros/LLNL Lawrence Livermore National Laboratory (LLNL) researchers are developing three-dimensional simulations to examine how a nuclear device could be used to deflect or potentially disrupt an asteroid threatening Earth.

Milky Way’s first microblazar candidate sits 12,000 light-years away, offering a rare ground-level lab for studying relativistic jetsA black hole 12,000 light-years away is firing a jet of plasma almost directly toward Earth. At that distance, no known or expected danger to Earth has been identified by the researchers or the institutions involved. What astronomers have actually found is rarer and more interesting than a threat. Researchers have identified IRAS 18293-0941 as a compelling candidate for the Milky Way’s first microblazar, a class of object that gives astrophysicists a close-up laboratory for studying some of the most violent physics in the galaxy. What Astronomers FoundThe discovery centers on a binary system whose black hole expels plasma jets at close to three-quarters the speed of light, pointed almost directly toward Earth. The system pairs a hot, massive star with a black hole that completes a full orbit roughly every 11.38 days. Material drawn from the companion star feeds the black hole, and some of that matter gets expelled outward as opposing jets traveling at approximately three-quarters the speed of light. Terminology matters here.