Popular Science Summer 2019

WHEN I WAS A KID, THE water cycle blew my mind. I think it was fifth grade science when I learned about the phenomenon through song (perhaps you did too), a musical description of how our planet turns moisture from everywhere into the water we drink. I remember it with a honky-tonk swing that I probably imagined. I’m absolutely sure about one thing: After the lesson, I walked up to the teacher to double-check the facts. “You mean we’ve got all the water we’re ever gonna get?” Yep, he replied. Kaboom. Worldview obliterated. This still amazes me. And water is just one of many resources we’ll never get more of. From the International Space Station to your flat-screen TV to carrots and horses and mason jars, all our planetary riches come from…

Mallory Pickett Before she became a freelance journalist, Mallory Pickett earned a Master’s degree in the chemistry of climate change. She’s captivated by the idea that our actions today will affect the Earth we’ll live on tomorrow—specifically, a warmer one. With aerosol particles and ocean acidification on her mind, she wonders what our planet could look like in the wake of the unnatural forces we’ve thrust upon it. “When we talk about climate change, it’s often this simple, monolithic thing,” she says. “But it’s unleashing this whole set of changes.” In her feature story on page 56, Pickett reports on an ecologically catastrophic algal bloom in the Gulf of Mexico that claimed the lives of sea creatures such as manatees, turtles, and dolphins. Its precise causes, and the role that climate…

MOST OF THE HUES WE LOOK AT THESE DAYS COME courtesy of 16,777,216 alphanumeric keys called Hex codes; tinting your technicolor digital life is as simple as copying a string of characters. But the shades on this page—and all your off-screen belongings—come from resources we must conscript to create our chosen chroma. Affixing color to an object (and making it stick) is tricky business. For most of human history, we’ve derived dyes from nature: People cooked plants and animals until they produced the desired pigment, or mined precious minerals from subterranean seams and ground them into paints. But even once we took to the lab to concoct new colors, some shades remained rarefied. This chart shows a few of the commodities that tint our kaleidoscopic world—and how long it took…

NOSTALGIC ABOUT BROWSING AT Blockbuster? Don’t be. Of all the ways to view a film at home, driving to a store to rent a copy consumes by far the most energy. It’s not exactly a Shyamalan twist to learn that gas-guzzling vehicles are bad for the environment. But what if we told you that streaming uses as much juice as getting a flick in the mail, old-school Netflix-style? An hour of streaming equals just over a week of light from a 10-watt LED bulb. The networks that supply zippy internet don’t run on movie magic—everything you do online has a carbon footprint. Here’s where each viewing method draws its power.…

THE EPA’S MOST RECENT census of U.S. waste tallied 262.4 million tons of new junk in 2015—the weight of about 40 Pyramids of Giza, or 4.5 pounds per person per day. We can recycle about one-quarter of what we toss, but rising costs and trade issues mean some municipalities no longer bother. Even in places that still attempt to keep trash out of landfills and oceans, not all “recyclable” items end up renewed. Here’s how much of that stuff actually makes it back into circulation—and why it’s smart to use fewer disposables, no matter what bin you put them in. Plastic plates and cups Most discarded dinnerware is made of polystyrene resin. It’s so cumbersome (bulky, but light enough to blow away) that no curbside pickups take it. We make use of…

STORAGE IS HARD TO come by aboard the International Space Station. Even if a rocket had room to ferry thousands of pounds of water and oxygen to supply a six-month mission, you’d struggle to find anywhere to stash it. So engineers have devised creative ways to squeeze essentials from astronauts’ sweat, urine, and breath. But we’re not at total recovery yet. Right now, the ISS recycles 90 percent of its water —or more than 1,000 gallons annually—and 40 percent of the oxygen astronauts breathe. The rest comes up on resupply missions. This diagram shows how NASA gets so close to a self-sustaining space home. 1 Astronaut An Earth-bound human uses about 80 gallons of water each day, but an ISS resident stretches just one for drinking, showering, and hydrating food. Astronauts’ bodies…