Tabla de contenidos para Summer 2021 en Popular Science

YELLOWSTONE NATIONAL PARK is stunning, yet even by that measure, the Grand Prismatic Spring astonishes. Sulfuric water, heated by the supervolcano beneath northwest Wyoming, burbles from a fissure 121 feet below the pool’s surface and radiates out 370 feet in concentric bands. Although hot enough to sear skin and scorch plants, the pond teems with heat-loving microbes called cyanobacteria. These organisms, among Earth’s oldest, have adapted to life in this hostile environment and give the popular attraction its signature hues. Here’s how they create a terrestrial rainbow. Blue At a scalding 189°F, the thermic feature’s aquamarine center is much too harsh for most life-forms. This renders the mineral-​rich H2O dazzlingly clear. But it appears azure for the same reason the ocean does: The translucent liquid absorbs red wavelengths and reflects…

Liquid metal The Equate Glass Oral Thermometer swaps the traditional mercury for a nontoxic blend of metals. It needs about three minutes to reveal the temp, but the analog method means you’ll never worry about a dead battery. Current The Kinsa Quickcare uses electrical resistance to measure temperature. A weak current runs through the gadget’s metal probe during its 8-second test; the slower those electrons move, the higher your fever. Light The iHealth Infrared Forehead Thermometer measures radiation coming off the skin 100 times per second. Two auxiliary sensors track the device’s distance from the patient and the ambient temperature to prevent faulty data.…

ON A GIVEN DAY in the area around Moab, Utah, visitors may view snowcapped mountains while gazing through a red-rock-desert arch that curves above a Grand-rivaling canyon. Or they might fish a river and then scale sandstone cliffs. Or perhaps they’ll wander a pine forest in the morning and uncover a dinosaur fossil after lunch. “There’s no one that’s seen it all,” says Russell von Koch, speaking of the vast and wild lands around the town he’s lived in for more than 30 years. He pauses, then says, “There are many out trying.” And he does mean “many.” Moab, with a population of just over 5,000, is a capital-D Destination for outdoor enthusiasts. Three million people visit every year. Some go because it’s the gateway to both Canyonlands and Arches…

GADGETS, LIKE PEOPLE, don’t like overheating. Running at excessive temps can decrease performance, damage components, and shorten a device’s life span. That’s why laptops use heat sinks, fans, and vents to modulate temperature, and most computers, phones, and tablets shut down when they begin to swelter. That said, prevention is the best strategy for avoiding long-term problems. On scorching days, keep your electronics off the ground and out of direct sunlight. Better yet, tuck them into the folds of a towel or stash them in a tote bag to block relentless rays. Juggling fewer tasks helps processors chill out, so shutting down power-hungry apps, disabling location tracking, and nixing Bluetooth and Wi-Fi can help. A temperature-monitoring app can keep tabs on things. You should start worrying when a gadget exceeds…

A WARMING WORLD will make summers increasingly uncomfortable, but that doesn’t mean air-conditioning bills need to rise too. For centuries, architects have helped folks brave the heat using tools like natural ventilation and passive cooling. The key is controlling how the structure interacts with solar energy. Designing with the sun’s rays in mind can keep a dwelling comfortable with minimal impact on the planet and the wallet, making staying cool a breeze. Summertime shade Deciduous trees block rays during the ice-cream-and-lemonade months, but let them through during winter. Awnings and overhangs also work. Building into a hillside provides cover and takes advantage of the soil’s insulation. Reflective roofs Insulating the roof or attic keeps the cold in and the hot out (and vice versa when days turn frigid). Light-colored shingles,…

Kiss cooler Ingesting sunblock is gross, but your lips can sear too. With flavors like pineapple and Key lime, the Sun Bum Sunscreen Lip Balm SPF 30 makes it more likely that you’ll cover your kisser. Face filters Maui Jim Onshore Sunglasses sport glare-killing lenses and a frame that curves to meet the contours of your face. The close fit prevents reflected light from roasting your eyeballs—which, yes, can burn. Cool cover-up A tight weave of recycled polyester gives the Patagonia SunshadeTechnical Hoody the best possible ultraviolet protection, stopping more than 98 percent of harmful rays. The hood offers plenty of room for a cap. Hoops goop Sweat obliterates sunscreen, but ThinkSport Safe Sunscreen can endure more than 60 minutes of hard exercise before wearing off because it contains 20…

For fast starts A series of precisely placed holes and air channels pull air through the Solo Stove Charcoal Grill’s stainless steel cooking chamber. That breeze allows it to go from cold to burger-​ready in just 10 minutes. For tailgating Weighing just 12 pounds, the Nomad IQ Portable Propane Gas Grill sports a 226-square-inch ceramic-coated bed of grates. It uses camping-style propane cans, so it starts quickly and spares you lugging bags of briquettes. For doing it all The Big Green Egg’s oblong ceramic chamber draws heat from a pile of charcoal burning in a firebox below. Its thick walls keep meticulously consistent temps whether you’re smoking a pork shoulder or charring a pineapple. For flame-kissed char You won’t find digital controls or Wi-Fi on the Grillworks Langelier Elite. A…

THEY LOOK LIKE MIRRORS: 32 rectangles neatly arranged in eight rows on the rooftop of a supermarket called Grocery Outlet in Stockton, California. Shimmering beneath a bright sky, at first glance they could be solar panels, but the job of this rig is quite different. It keeps the store from overheating. Tilted toward the sun, the panels absorb almost none of the warmth beating down on them; they even launch some into space, improving the performance of the systems that keep things inside cold. The feat relies on a phenomenon called radiative cooling: Everything on Earth emits heat in the form of invisible infrared rays that rise skyward. At night, in the absence of mercury-raising daylight, this can chill something enough to produce ice. When your car’s windshield frosts over,…

EARTH IS EVER SHIFTING. Continents drift, ice ages come and go, odd and wonderful creatures take shape only to one day vanish. Reviewing the history of our world, some might be tempted to dismiss the warming we are experiencing as just another of these planetary ebbs and flows. Yet scientific consensus is clear: Not only is the climate rapidly changing, but humans are to blame. Each decade for the last 40 years has replaced the preceding one as the hottest on record, and historical data proves this acceleration isn’t natural. But decadal temperature increases are hard to feel. Here are some signs that Homo sapiens are behind this trend, and a couple of effects you can feel yourself. A / Fossil-fueled skies Since 1800, global CO2 levels have climbed more…

SINCE ITS FORMATION IN 1983, Kīlauea’s Pu‘u‘ō‘ō cone had risen and fallen as magma fluctuated throughout the volcano’s vibrant East Rift Zone. But on April 30, 2018, Pu‘u‘ō‘ō announced its retirement with a rumble. The once-brimming basin drained down into the earth like an unclogged sink. Newly liberated lava crept from the summit toward the Big Island’s eastern tip. Soon Leilani Estates, a community of around 2,000, would confront the eruption firsthand. Fissures exploded with ash, noxious gas, and molten lava across roads and into backyards. Pu‘u‘ō‘ō’s swan song ultimately destroyed some 700 homes. Then the foundation of the Hawaiian Volcano Observatory (HVO)—​established by the US Geological Survey (USGS) in 1912—began to crack. On May 16 the staff was forced to evacuate. “We scattered to the winds and took what we…

IN THE ANIMAL KINGDOM, tempting a mate appears easy. Male peacocks unfurl their sexy feathers when they spot a would-be love. Spiders woo with the erotic gift of dead insects. For humans, the prospect of such a simple path to achieving hotness can be mighty tantalizing. But can science identify a shortcut to that initial spark and a key to fanning the flames of a successful relationship? Probably not. But that hasn’t kept everyone from the ancient Greeks to modern psychologists and anthropologists from searching. While neuroscientists have identified a behavioral “attraction system” that seems to activate nerve cells in the midbrain to release the oh-so-pleasurable neurotransmitter dopamine when we’re into someone, they still don’t understand why only some potential mates spur activity. Over thousands of years, people have landed…

TG Plasma lighter Rather than relying on butane to create a flame like Granddad’s trusty fire starter, this 3.5-ounce torch makes its own lightning. An electrical current creates high-voltage arcs between four electrodes, generating more heat than flicking a Bic. überleben Zünden Fire Starter The recipe for flames is simple: Gather tinder, add spark. Drag this tool’s blunt edge across the 5⁄16-inch-diameter rod—made of ferrocerium, an alloy used as the “flint” in lighters—to create a 5,500-degree shower of burning metal. Zippo Typhoon Match Kit Most matches use a small dab of red phosphorus to get started. The extra-​thick coating of it on these 4-inch wonders lets them burn for up to 30 seconds, even in wind or rain. The watertight plastic case holds up to 15 and boasts a replaceable…

JÖRN HELBERT was standing outside a stranger’s apartment in the north end of Berlin with a bouquet of yellow roses. It was June 2020, and the woman behind the door was in mandatory quarantine. She had just moved to Germany from the United States, and as a favor to Helbert, a fellow planetary scientist, she was acting as a courier, bringing rocks far too precious to be put in the care of international postal systems hopelessly backlogged because of the pandemic. Already one shipping snafu had sent the package to a nail salon in Tucson and nearly lost it. Helbert was familiar with the kind of questioning you might run into when carrying geologic samples through German customs, so the flowers were a gift for her trouble. The handoff had…

IT BEGINS WHEN YOU STOP SWEATING. Perspiration usually cools you down by releasing heat into the air as sweat evaporates, but eventually, if your body becomes dehydrated or the external mixture of hot air and humidity gets too high, you can no longer push the salty liquid through your pores. You flush all over as blood moves toward your skin—an attempt to shuttle warmth away from your core. Muscles cramp up as your salt reservoirs deplete. Organs swell as your body kicks up an immune response. Your thinking gets fuzzy. You might start hallucinating. You vomit so your stomach can stop wasting energy on digestion. Your heart pounds and your head aches. You may begin to have seizures. When death finally comes, whether within the hour or a few days…

ROBERT HUTCHINGS GODDARD always had rockets on the brain. Of the early-20th-century inventor’s 214 patents, the vast majority focused on catapulting us into space; those that didn’t still had astronomical inclinations. One such invention, published in Popular Science in November 1929, was for a solar generator to “supply abundant and cheap power” that could prove useful on Earth but that Goddard admitted he mainly intended for “interplanetary navigation.” Unlike photovoltaics, which generate energy when the sun’s rays liberate electrons from light-sensitive materials, Goddard’s scheme concentrates light so it can boil water in a turbine. While Goddard did not invent the concept—known as either solar-thermal power or concentrating solar power (CSP)—​he set in motion improvements that have helped make it a contender in our growing renewables arsenal. The first CSP installation, opened…