Indholdsfortegnelse for March/April 2025 i Popular Mechanics

BNETELGEUSE (NOT BEETLEJUICE, THE slimy character of movie fame) is one of the most celebrated celestial objects in the night sky and has been at the heart of several mysteries over the years. For instance, the star goes through periods of brightening and dimming, usually in a 400-day cycle. But in 2019, it experienced a big change in luminosity known as “The Great Dimming.” Because of this unexpected dimming, scientists at the time pondered if perhaps the star was dying, but it turned out that the star was just off-loading lots of dust and gas. Since then, the star’s luminous heartbeat has quickened, and it jumped in luminosity just last year. Betelgeuse also experiences a second kind of heartbeat known as a “long secondary period,” or LSP, which lasts roughly six…

“THERE IS NOTHING LIKE LOOKING, if you want to find something,” says Thorin Oakenshield in J.R.R. Tolkien’s beloved fantasy novel The Hobbit. “You certainly usually find something, if you look, but it is not always quite the something you were after.” For example, in 2015, researcher Ludovic Slimak made a remarkable discovery. He and his team had been working for some time to find remnants of humanity’s prehistoric forebears, and they certainly found something: a piece of a Neanderthal jaw. Eventually, several more remains of this Neanderthal were discovered. Slimak told the New Statesman in 2022 that each year after the initial discovery, they would find “one tooth, or one fragment of bone.” Slimak determined that this particular Neanderthal lived 42,000 years ago. He named the Neanderthal Thorin after the Tolkien…

On the evening of MARCH 20, 1948, Air Force meteorologist Captain Robert Miller arrived for his forecasting shift at the weather station on Tinker Air Force Base, a sprawling installation roughly five miles east of downtown Oklahoma City. After analyzing the latest weather maps and charts received via fax from Washington, D.C., Miller predicted that aside from occasional gusts of wind, the base was in for a “dull night.” It would soon be clear just how far off the mark that prediction was. Around 9 p.m., weather stations to the west of Tinker began reporting lightning. A half hour later, even Miller’s crotchety AN-PQ-13 radar—which had been stripped from a World War II–era B-29 and repurposed as a meteorological instrument—was picking up thunderstorms that, as he later recalled, “looked vicious and…

Scientists recently analyzed Vincent van Gogh’s Starry Night to see how well its famous swirls matched up with known atmospheric physics. After analysis, they found that not only did the shapes match up with our current ideas of atmospheric turbulence, but the colors used throughout the piece communicated fairly accurate physics at a remarkably small scale. The team released their findings in a study published in the journal Physics of Fluids. Yongxiang Huang, PhD, one of the authors of the paper, thinks that van Gogh could have come to understand these movements by “studying the movement of clouds and the atmosphere," or that he could have just had “an innate sense of how to capture the dynamism of the sky.” LANE OF POPLARS AT SUN-SET → Starry Night is not the…

FOR OVER 100 YEARS NOW, QUANTUM mechanics has rattled the cage of everything we’ve known about physics. Is everything just made of wiggles and waves if you look closely? How far can one entanglement be stretched—is it long enough to enable quantum telecommunications? And those questions don’t let up when it comes to reality or realism. We know that a quantum particle doesn’t have a true state until it is observed (à la Schrödinger’s cat), but the question behind that fact persists for all things in existence—does an object still have properties when those properties are not being observed? At a certain point, this foundational question becomes…well, entangled…with an additional concept called locality. Locality describes whether or not an object is influenced by more than its own immediate physical surroundings. If…

THE year is 72 B.C.E., and the Roman Republic has already punched a one-way ticket toward empire. The evergrowing Mediterranean power is embroiled in yet another conflict, and the Roman conqueror Lucius Lucinius Lucullus has chartered a series of ships to ferry home riches from newly plundered regions. Although most ships eventually reach their destination at the port of Ostia, southwest of Rome, one Greek ship—loaded with jewelry, coins, statues, glassware, and bronze masterpieces—never arrives. As the vessel traverses the Aegean Sea, a violent tempest tosses it into the rocky shores of an island called Antikythera. The collision tears into the ship’s five-inch-thick hull, causing it to sink more than 100 feet beneath the waves until finally resting on a submerged slope off the island’s coast. This is the story—or…

THE SANDSTONE CLIFF FACES OF THE ancient city of Petra (one of the New Seven Wonders of the World) have long been in the archaeological limelight. They’ve even spent time in the Hollywood spotlight as the location for several scenes in the film Indiana Jones and the Last Crusade. But in their most recent on-screen appearance—and no offense to Harrison Ford’s iconic professor—they were the site of a very real discovery. Discovery Channel’s popular show Expedition Unknown was recently on-site to document the discovery of 12 human skeletons and artifacts dating back at least 2,000 years, which had all been long hidden beneath the famed Khazneh (or “Treasury”) in Petra. The colossal find was accomplished by a team led by archaeologist Pearce Paul Creasman. “This is a hugely rare discovery,” said…

For a recent project, we needed a large 1¾"-thick piece of solid black walnut. You won’t find wood like this just anywhere, and when you do, it’s rarely in the dimensions you need. The problem with thicker slabs of specialty wood is that they’re often found “rough-cut” from the sawmill, anywhere from 1", 2", 2½", or 3" thick, and not dimensionally consistent. In these cases, if you don’t have a large commercial planer at your disposal, you’ll need to get the wood milled to your specifications. Or, you can build a slab-flattening sled that will enable you to achieve a smooth, level surface yourself instead of paying someone to mill it for you. WHAT IS A ROUTER SLED? In simplest terms, a router sled is a device that facilitates movement…