Astronomers Just Found the First Green Star Ever Discovered—Right After It Swallowed Its Planets - Gizmodo

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.

Most people know planets are objects that go around a star, just like Earth goes around the Sun. Rogue planets are objects that have mass similar to planets but are not orbiting stars.