October 24, 2024: We're living in the golden age of apples. Plus, microbes that break down "forever chemicals," and the longest black hole jet ever observed. —Andrea Gawrylewski, Chief Newsletter Editor | | | An artist's illustration of the longest black hole jet system ever observed. Nicknamed Porphyrion after a mythological Greek giant, these jets span roughly 7 megaparsecs, or 23 million light-years. E. Wernquist/D. Nelson (IllustrisTNG Collaboration)/M. Oei (CC BY-NC-ND) | | | • In a galaxy 7.5 billion light-years away, astronomers spotted a supermassive black hole shooting out streams of magnetized plasma as far as 140 Milky Ways in length--the longest jet ever observed. | 8 min read | | | • In his new book, political correspondent Peter Schwartzstein explores how climate change pulls societies apart and feeds violence. | 7 min read | | | • This is the lost story of chemist Dora Richardson, who created the life-saving cancer drug tamoxifen. | 41 min listen
| | | Apple varieties grafted to dwarf rootstock shown here start to fruit years before those grown on larger rootstock. Birkus-Viktor/Getty Images | | | What's your favorite kind of apple? There are so many excellent varieties now, most of them available only since the turn of the millennium–some grocery stores carry 20 varieties in-season, twice as many as a decade ago. This golden age of apples comes from consumer demand; dedicated and creative pomologists (fruit scientists); and long-term research at the U.S. Department of Agriculture, universities, and research stations and growers around the world. New technologies, rootstocks, breeding methods and genetic research have changed the apple experience: Cosmic Crisp, Honeycrisp, SnapDragon and more are replacing the old Red Delicious (are they actually delicious though?). Email us your favorites and we'll share them in a future newsletter.
How they did it: Apples don't self-fertilize–they need the pollen from other trees, which bees bring. To create new varieties, scientists throw a net over certain trees with desirable apple traits and hand-fertilize their flowers with the pollen from another variety of apple. The first tree produces apples, and the pomologists collect the seeds from those fruits and sprout them into seedlings and test their genetics for desirable traits. Only then are select plants allowed to grow. Sounds like a laborious process, but the end result is you can hold a pinnacle of human achievement in your hand and take a bite!
What the experts say: There's no device or test that can tell how delicious an apple is. Humans have to bite into each new variety to decide whether it's worth developing. "At the peak of crunch times, I've had to taste 600 apples a day," says David Bedford, an apple researcher at the University of Minnesota. "The first 100 are okay, but after that, it gets to be real work." –Laura Helmuth, editor in chief | | | Researchers screened microbe communities living in wastewater and found four strains of Acetobacterium that could digest "forever chemicals," or PFASs for perfluoroalkyl and polyfluoroalkyl substances. The bacteria produce an enzyme that breaks down PFAS molecules into smaller fragments over the course of several weeks.
Why it matters: PFASs represent nearly 15,000 chemicals found in everyday products from rain jackets to pizza boxes, and have been detected in the blood of nearly everyone. The chemicals have been linked to different types of cancer. Though researchers have discovered other microbes that can break down the harmful substances, those organisms are slow to grow and are finicky about their conditions.
What the experts say: The Acetobacterium lines target a specific group of PFAS, so scientists' next step is to engineer the microbes to digest other kinds of forever chemicals, and ideally be used in combination with other PFAs-destruction methods (like heat or high pressure), says Yujie Men of the University of California, Riverside. | | | • Are election polls accurate? "Too often journalists, politicians and the public treat polls as cheat codes to the election casino, revealing ahead of time whether to play red or black," writes David Dutwin, senior vice president of strategic initiatives at NORC at the University of Chicago. But polls ask how people would vote "if the election were held today," and so are capturing a moment in time. "Even polls conducted a few days before the election cannot compensate for momentum in the final week and have a limited ability to peer into the minds of the undecided, who often number enough to swing results," he says. | 5 min read | | | Amanda Montañez; Source: Hans-Karl Eder/Spektrum der Wissenschaft (reference) | | | • Math puzzle: Let's say you built these five houses of cards using a total of exactly 90 playing cards. Now you want to build one large house consisting of exactly 100 cards. Can such a house of cards exist? For the solution, click here. | | | I still remember the first Honeycrisp I bit into--it was nothing like the boring and often mealy offerings found in most supermarkets. Once you have a truly delicious apple, you can never go back to the waxy norm. Other standouts I've discovered over the years: Pink Lady, Ambrosia, Macoun and Jonagold. What are your favorites and where do you get them? | —Andrea Gawrylewski, Chief Newsletter Editor | P.S. Yesterday, we erroneously said that a mole was a rodent. Several sharp-eyed readers wrote in to remind us that moles are in fact insectivores, part of the same animal family as shrews. | | Subscribe to this and all of our newsletters . | | | | Scientific American
One New York Plaza, New York, NY, 10004 | | | | | | Support our mission, subscribe to Scientific American | | | | | | | | | |
