“Today in Science:  Is it safe to fly during FAA flight restrictions?”

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November 7, 2025—Today, a confession from our columnist, astronomer Phil Plait. Plus, graphs show how diabetes rates are soaring globally, and what the FAA’s flight reductions mean for your travel plans and safety. —Andrea Gawrylewski, Chief Newsletter Editor TODAY’S NEWS NOAA An Arctic cold-snap will move into the eastern U.S. early next week, potentially breaking records, especially in southeastern states. | 2 min read How will the FAA’s 10 percent reduction in flights affect safety and your travel plans? We asked an expert. | 4 min read While exploring a cave on the Albania-Greece border, scientists found the largest spider web ever recorded: more than 1,040 square feet —nearly half the size of a tennis court. | 2 min read Three Chinese astronauts are temporarily stranded on the Tiangong space station after a piece of space junk struck the Shenzhou 20 spacecraft which would have ferried them back to Earth. This space junk is becoming a real problem. | 4 min read More News Explore the universe and feel the awe of science. Subscribe to Scientific American with a special discount for Today in Science readers. TOP STORIES Below is an excerpt from the latest edition of The Universe, a weekly column by astronomer Phil Plait. I think you’ll love Phil’s unique and insightful (and sometimes cheeky!) coverage of the cosmos. Sign up for an alert and read it first.   This image derived from Gaia data shows an edge-on view of our galaxy. ESA/Gaia/DPAC, S. Payne-Wardenaar, E. Poggio et al (2025) A Warped View So it’s confession time: I’ve been lying to you. I’ve said on many occasions that our Milky Way galaxy has a flat disk (like in this column or this one). But it’s not really flat—not even for a reasonable definition of the term. Now, in my defense, I wasn’t lying per se; I was simplifying. That’s a perfectly acceptable and even advantageous thing to do in science. When you have some complex thing that you’re trying to understand or explain, it helps to make it as simple as possible so that the math and physics are easier to crack. It’s like assuming, at first, that Earth is a perfect sphere or that the sun contains all the mass in the solar system. Once you work out the basic equations that describe your simplified model, you can gradually add complexity back in—but in a way that makes the problem tractable. And to be fair, when you look at the glow of the Milky Way from a dark site, it does look flat—flat-ish. And lots of similar galaxies and their disks also appear flat. But a lot of them, maybe even most of them, aren’t. They’re wiggly and wavy and bendy. Our galaxy is among this warped group. First, a quick overview: the Milky Way is classified as a disk galaxy, with a broad circular collection of stars, gas and dust about 120,000 light-years across. It’s a few thousand light-years thick, so “flat” is at least a decent adjective to use for it. In the center is a central bulge of stars, and the whole thing is surrounded by a vast halo of stars and dark matter about a million light-years wide. That last bit is important. Hang on a minute, and I’ll explain why … Read the rest of Phil’s column here, and sign up in the blue box at the top of the article for an email alert and read it first every week.  Diabetes Soaring More than 9.5 million people around the world have Type 1 diabetes—and the number is soaring. But scientists aren’t completely sure why. Improvements in diagnostic tools and awareness may be driving some of this growth. Still, cases are rising relative to population size, regardless of the country’s income status, and in young and old people alike. This reflects a general rise in cases and earlier diagnosis. Why it matters: The burden of this autoimmune disease is not equally distributed. The condition is more lethal in low-income countries, where hospitals and clinics are less equipped to detect and manage the disease. A 10-year-old with T1D in the United Arab Emirates can expect to live more than 50 years longer, on average, than a 10-year-old with T1D in Niger. What the experts say: “Type 1 [diabetes] is being diagnosed more than it ever has been before, but you need more in-depth studies to understand why these numbers continue to rise,” says Stephanie Pearson, senior director of global responsibility at the nonprofit Breakthrough T1D. Today, scientists are exploring a few possible explanations, including biological triggers, infections, diet, lifestyle choices and even factors related to pregnancy. —Andrea Tamayo, Newsletter Writer    Read more about type 1 diabetes in this special report.

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PLAY NOW Test how well you read Scientific American this week by taking today’s science quiz. Plus, here’s today’s Spellements puzzle and an extra challenging version of Sudoku (we call it Killer Sudoku). More Games MOST POPULAR STORIES OF THE WEEK COVID Is Beginning to Surge Globally. Here’s What We Know | 4 min read Catch the Taurid Meteor Shower—And Learn Why Scientists Are Watching It Closely | 4 min read Why We Struggle to Say No—And How to Get Better at It | 17 min listen In his most popular column so far this year, Scientific American contributor and astronomer Phil Plait considers whether any life on Earth can survive the death of the sun. He gives a lively play-by-play of how the sun’s natural aging process will affect Earth in about 3 billion years. Long story short, it’s not pretty and if humans are still around, we’ll have to relocate to another solar system. “Packing up and moving is never fun,” he writes, “but if your house is on fire, there’s not much choice.” I highly recommend you sign up for Phil’s column alerts, he brings a levity to complex cosmological concepts that is a true delight. Have a great weekend and see you Monday. You can email me anytime with your thoughts or ideas for how to improve this newsletter: newsletters@sciam.com. —Andrea Gawrylewski, Chief Newsletter Editor

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“Today in Science:  Something is happening to Earth’s glow.”

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 22 October 2025, 2041 UTC.

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October 22, 2025—Today, a strange thing is happening to the blue marble, fish evolution is outsmarting humans, and Google’s quantum computer chip explores chaos. —Andrea Gawrylewski, Chief Newsletter Editor TODAY’S NEWS Google’s Willow quantum computer chip. Google Quantum AI Google’s quantum computer chip Willow explores “quantum chaos” by scrambling and unscrambling information. It could lead to advances in molecular chemistry and the physics of black holes. | 4 min read Science can explain why some apologies ring hollow and others seem genuine. | 11 min listen Your brain gets used to wrongdoing. It can also get used to doing good. | 17 min read An inside look at how the world’s most famous code, the CIA’s Kryptos puzzle, got cracked. | 7 min read More News Supporting our work means amplifying science. Consider a subscription to Scientific American and back independent science journalism! Today in Science readers can get started for just $1. TOP STORIES Different surfaces like ice (shown here), water and clouds reflect varying levels of sunlight. NASA/Goddard Space Flight Center Conceptual Image Lab Darkening Earth Scientists examined data over a 24-year period from three satellites measuring incoming sunlight against the amount of radiation reflected back into space from the surface of Earth. They discovered that the brightness of Earth is dimming, and the Northern Hemisphere is darkening more than the Southern Hemisphere. Scientists hypothesize that 1) increased warming in the Northern hemisphere from loss of highly reflective sea ice may be partially responsible, and 2) fewer reflective aerosols in clouds in the Northern Hemisphere mean more sunlight penetrates the atmosphere (recent volcanic activity and the Australian bushfires in the Southern Hemisphere has led to more cloud-bound aerosols). Why this is matters: If less sunlight is reflecting off clouds and the surface in the Northern Hemisphere, more heat will melt more ice, furthering global warming. What the experts say: Because of the imbalance in reflectivity, “the whole circulation of the climate will shift in order to transport energy from the hemisphere that has a surplus to the one that has a deficit,” says Brian Soden, a University of Miami professor of atmospheric science. This could influence ocean currents and the location of rainfall bands, which can have ramifications for water availability. Bass Backlash A population of invasive smallmouth bass in Little Moose Lake in New York have genetically outmaneuvered the 20-year culling campaign by a group of Cornell University scientists. Genetic tests revealed that the overpopulating fish have evolved to grow faster and spawn younger. The new adaptations let them reproduce before the scientists take their twice-yearly lake cruise to electrically cull and remove the fish. The lake’s bass population is thriving at larger numbers than ever. How this works: Scientists sequenced DNA samples of the fish and found that the genes of the chromosomes involved in growth rate and reproduction timing were “wildly different” from those in tissue samples taken from Little Moose bass preserved before the electrofishing began, says Liam Zarri, a molecular ecologist at the Smithsonian National Zoo and Conservation Biology Institute. Individual bass with genes that lead to late sexual maturity and slow growth didn’t survive to reproduce before the shock treatments. Instead, the bass that were genetically predisposed to live fast, reproduce early, and die young were more likely to spawn. What the experts say: The timing of the cullings is fueling the fishes’ genetic adaptation, so varying the culls’ timing and frequency could slow the rapid evolution, says Stephanie Green, an ecologist who wasn’t involved in the research. The Cornell scientists say they’re actively considering such alternatives. —Andrea Tamayo, Newsletter Writer

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“Which anti-inflammatory supplement actually works?”

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 17 October 2025, 0256 UTC.

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October 16, 2025—Which anti-inflammatory supplements are worth your time? Plus, a concerning cancer trend among women, and the government shutdown is hurting science. —Andrea Gawrylewski, Chief Newsletter Editor TODAY’S NEWS Filo/Getty Images (images); Scientific American (animation) A mathematical principle called Parrondo’s paradox explains how combining losses can lead to a win. It may aid scientific discovery in biology and cancer research. | 5 min read The U.S. government shutdown is starting to pinch science: projects at several federal museums and laboratories have been suspended, public health workers have been fired, and funding cancelled to clean energy research. | 5 min read OpenAI’s recently-released Sora app may be the start of a new digital economy for deepfakes. | 3 min read Wood burial, also called wood vaulting or biomass burial, could potentially store more than 12 billion tons of carbon dioxide every year. | 5 min read More News Science matters. Support science you can trust with a subscription to Scientific American. Today in Science readers can get started for just $1. TOP STORIES Anti-Inflammatory Supplements Supplements to fight inflammation are a booming business. These pills, capsules and powders are projected to become a $33-billion industry by 2027. Although thousands of products claim to “support immunity” or “reduce inflammation,” most lack solid evidence. Scientific American reviewed dozens of studies and spoke with researchers to find out whether any supplements demonstrate anti-inflammatory activity not just in laboratory animals and cultured cells but in human trials. Just three compounds, it turns out, have good evidence of effectiveness: omega-3 fatty acids, curcumin and—in certain ailments—vitamin D. What we looked at: Scientific studies vary in how they’re designed and carried out. We looked for consistent results across several studies that scientists described as large and well designed. Ones that passed muster tended to focus on biomarkers that researchers use to track inflammation in the body. These include C-reactive protein (CRP), a molecule produced by the liver when inflammation is active, and cytokines, which are chemical messengers. For example, omega-3 fatty acids, which have the most compelling evidence behind them, come in two forms, and they signal the production of molecules in the body that block certain cytokines associated with inflammation. What the experts say: Inflammation involves hundreds of different types of cells and many signaling pathways, says Prakash Nagarkatti, director of the National Institutes of Health Center of Research Excellence in Inflammatory and Autoimmune Diseases at the University of South Carolina. This complexity makes it difficult to prove that any supplement works consistently. WATCH THIS Jeffery DelViscio/Scientific American; Getty Images A Concerning Trend Lung cancer is the deadliest cancer among women in the United States, surpassing the mortality numbers of breast and ovarian cancer combined. And surprisingly, younger women who have never smoked are increasingly being diagnosed with the disease. What’s going on? Science, Quickly host Rachel Feltman sat down with Jonathan Villena, a thoracic surgeon at NewYork-Presbyterian and Weill Cornell, to try to get to the bottom of it. Watch the whole interview here.

EXPERT PERSPECTIVES No federal agency in the U.S. fully oversees the clinical testing and chemical verification of supplements or nutraceuticals (pills and powders derived from foods that make various health claims), and these products are often plagued by quality and safety problems (and are associated with tens of thousands of ER visits a year). Congress should empower the Food and Drug Administration to start treating these products more like drugs, which undergo stringent testing and regulation, the editors of Scientific American wrote in 2023: “The FDA should be empowered to verify nutraceutical products by chemically confirming their ingredients, enforcing recalls and product bans, and maintaining a publicly searchable database of all supplement and nutraceutical health products with their associated ingredients and efficacy studies.” | 3 min read SCIENTISTS AT WORK Andrea Varela Conservation biologist Amy MacLeod runs a program called Iguanas from Above, which uses drones to study the population of marine iguanas (Amblyrhynchus cristatus) on the Galápagos Islands. Bolstered by 17,000 online volunteers, the project has now surveyed the whole archipelago, some parts of which were previously inaccessible. “I’m proud that the use of drones for wildlife survey is now a tool that other scientists can test in remote places around the world,” she says.​ Nature | 3 min read Content courtesy of Nature Briefing You may be asking yourself why store shelves are filled with so many supplements in the form of pills, powders or tonics claiming to be anti-inflammatory or “detoxing” if they’re not all effective at what they claim. Here in the U.S., supplements are largely self-regulated under loose post-market oversight, whereas in other places, like the European Union, dietary supplements face the same kind of scrutiny as food—ingredients and health claims must be proven safe and authorized before they hit the market. This means the responsibility for judging what’s safe or effective often falls to the consumer—and, ideally, an informed doctor. Thanks for reading. Send comments or feedback on this newsletter to: newsletters@sciam.com. See you tomorrow! —Andrea Gawrylewski, Chief Newsletter Editor

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“Today in Science:  Record-breaking Everest blizzard explained.”

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 09 October 2025, 2054 UTC.

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October 9, 2025—Do pets improve our health? Plus, how birds responded to the 2024 total solar eclipse, and the latest COVID vaccine is effective for all age groups. —Andrea Gawrylewski, Chief Newsletter Editor TODAY’S NEWS A greater noctule bat caught in a mist net with a passerine feather and blood in its mouth. Jorge Sereno Bat vs. robin: This bat pursues, kills and eats a migrating European robin—all in midair and while echolocating to navigate. Holy midair mayhem, Batman! | 3 min read Scientists took 300,000 videos of cats to train an AI litter box that monitors cats’ health. | 5 min read A blizzard that trapped hundreds of trekkers on the north side of Mount Everest last weekend was truly bizarre: the amount of snow that fell within 12 hours was 3.5 times greater than anything measured at the mountain before. | 3 min read Receiving an updated COVID vaccine reduced people’s risk of severe disease and death in all age groups, regardless of immunity from prior infection or vaccination, according to a new study. | 3 min read This year’s Nobel Prize in Physics honored scaled-up quantum physics—while sidestepping controversies and hype swirling around quantum computing. | 6 min read More News Science matters. Support science you can trust with a subscription to Scientific American. Today in Science readers can get started for just $1. TOP STORIES Pet Benefits Does owning a pet improve health? Many recent studies have found that yes, pets have a positive influence on our lives. In one study, 43 dog owners performed stressful tasks (like public speaking) with and without their pets. Those who had dogs accompany them showed lower spikes of cortisol, a hormone that rises under stress. In another study of 90 older adults, about half were given five crickets to care for. Adults who cared for the insects made improvements in mental and cognitive health, while the other half didn’t. Why this is interesting: For the older adults who looked after the crickets, having a pet may have added a sense of purpose, says Jessica Bibbo, a gerontologist who studies human-animal interactions. On top of this, there are several consistent positive effects in owning a pet: owning a dog, for instance, is associated with increased physical activity (a great health boost). However, not all studies find a strong link between pet ownership and better health. The quality of the relationship between humans and their animals might be a better predictor of positive outcomes than just the fact that pets are in the home. What the experts say: “Pets are not a medical intervention; they’re a relationship,” says Jessica Bibbo, a gerontologist who studies human-animal interactions. Even therapy animals are there to facilitate, not to fix, Bibbo says. People emphatically believe pets improve our quality of life, and that belief can affect health, even if indirectly. —Andrea Tamayo, Newsletter Writer Birds, Eclipsed During the April 2024 total solar eclipse, bird behavior shifted dramatically in the four minutes of darkness. Using data provided by nearly hundreds of community scientists and AI analysis of about 100,000 recorded bird calls during the eclipse, researchers discovered that some species’ vocalizations spiked during totality while activities like flying and feeding dropped. In total, 29 of the 52 species analyzed showed changes in their singing in at least one of the three time periods—before, during or after the eclipse—suggesting a widespread but species-specific sensitivity to light. Once sunlight returned, many species began singing again as if it were dawn. Why this is interesting: Animal behavior is tied to natural light cycles, and the study shows that even brief disruptions can affect their biological rhythms. The results could help identify species most vulnerable to artificial light pollution. The eclipse also offered a chance to join professional and amateur bird observers in a huge natural experiment. What the experts say: This new study provides a “rich and unique new dataset” to challenge what scientists think they know about how birds of different species respond to radical changes in light, says ornithologist Andrew Farnsworth of Cornell University. “There might be additional kinds of behaviors that are probably buried in their recordings and that the authors are going to be able to analyze further.” —Humberto Basilio, News Intern

EXPERT PERSPECTIVES In July, the FDA convened a panel on the use of the class of antidepressants called selective serotonin reuptake inhibitors (SSRIs) during pregnancy. “The FDA panel tried to discredit the past years of research on SSRIs, the most studied category of medications in pregnancy, stoking fear over these drugs,” writes Catherine Birndorf, a reproductive psychiatrist and associate professor of psychiatry at Weill Cornell Medicine. “Untreated depression and anxiety during pregnancy are far more dangerous—to both parent and baby—than carefully managed antidepressant treatment,” she says. | 5 min read SCIENTISTS AT WORK Mahé Elipe Biologist Carmen García-Chávez is the co-founder of a charity that works to recover the population of the Mexican wolf (Canis lupus baileyi), which had been hunted to near-extinction by the 1980s. Her work involves outreach to local landowners and communities to discuss benefits that can come from reintroducing the species. “I’ve watched children explain to their parents why ‘the wolf is not the bad guy,’ but a valuable animal that helps maintain the balance of the ecosystem,” she says.​ Nature | 3 min read Content courtesy of Nature Briefing I think most people would quickly agree that their pets improve their health. Some studies have found that listening to a cat’s purr can lower blood pressure, and the companionship of animals can give people hope and purpose, not to mention the life-saving benefit of alert dogs for certain illnesses like epilepsy and type I diabetes. Even without the data, the loss of a beloved friend reveals how much they imbue our lives with meaning. Thanks for reading. Send comments or feedback on this newsletter to: newsletters@sciam.com. See you tomorrow! —Andrea Gawrylewski, Chief Newsletter Editor

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“5 tips for avoiding scams.  Will AI ever win its own Nobel Prize?”

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 08 October 2025, 2207 UTC.

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October 8, 2025—Chemical cages win the Nobel Prize in Chemistry. Plus, how to avoid scams and astronomers pick their favorite exoplanets. —Andrea Gawrylewski, Chief Newsletter Editor TODAY’S NEWS An exoplanet orbits a star, in an artist’s depiction. ESO After 30 years of hunting for alien worlds, astronomers choose their top five favorite exoplanetary systems. | 4 min read We sit down with former astronaut Chris Hadfield to talk about his new book—a thriller called Final Orbit, which weaves together real cold war history, space race geopolitics and firsthand experience. | 11 min listen Will AI ever win its own Nobel? Some experts predict it could happen soon. | 8 min read Most-clicked yesterday: Prime Numbers Show Unexpected Patterns of Fractal Chaos | 5 min read More News Supporting our work means amplifying science. Consider a subscription to Scientific American and back independent science journalism! Today in Science readers can get started for just $1. TOP STORIES Molecular Cages Win the Nobel The 2025 Nobel Prize in Chemistry has been awarded for a versatile technology that can be used for an astonishing variety of purposes, from environmental remediation to drug delivery and energy storage. Susumu Kitagawa, Richard Robson and Omar M. Yaghi shared the award for their development of metal-organic frameworks (or MOFs), chemical cages that have small openings that can capture a diverse array of other small molecules. How it works: The cages are made of metal ions held together by organic, or carbon-containing, molecules. The cages can be one-dimensional or multi-dimensional, and they can be formed from a host of metals and organic linkers. Unlike polymers that grow in only one direction, MOFs build out as crystals in all directions. They have a very rigid, uniform, and precise arrangement of atoms. Why this matters: MOFs are being explored for their use in wastewater cleanup, PFAS removal, timed or multi-drug release systems, and more. Some experts say that MOFs could be used for soundproofing and sensors, or to pull carbon from the atmosphere. Avoiding Scammers Every year, millions of adults lose their savings to scams (estimated annual losses of nearly $28 billion in the U.S. alone), but seniors are especially vulnerable. Scammers take advantage of the many challenges that come with aging, including cognitive decline, changes in life circumstances (such as the death of a spouse), and difficulty keeping up with evolving technology. Additionally, artificial intelligence has introduced new ways to scam people through replicated voices, videos, photographs and documents. But there are many ways to reduce the risk, research shows. How to avoid scams: Criminologists Thomas Blomberg and Julie Brancale conducted surveys with hundreds of older adults and pinpointed practical steps people can take to avoid becoming a victim. Here are five of the many tips they share: 1. Resist pressure to act quickly. 2. Be suspicious of unsolicited telephone calls, mailings, online interactions or door-to-door services. 3. Never send personal identifiable information, money, jewelry, gift cards, checks, or wire funds or information to unverified persons or businesses. 4. Never open an e-mail attachment or click a link in a text message from someone you do not know. 5. Create a secret family password to verify the identity of a family member to use in the event you receive suspicious telephone or online requests for money for personal information. Why this matters: By inciting panic and inducing isolation, scammers targeting older people push them to make decisions alone and quickly. Not to mention the financial loss, these events can damage mental and physical health, erode self-confidence, diminish one’s quality of life, and even contribute to premature death. —Andrea Tamayo, Newsletter Writer

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“Today in Science:  How many people have lived on Earth?”

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 03 October 2025, 2109 UTC.

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October 3, 2025—We’ve crossed another planetary boundary, some galaxies are moving faster than the speed of light, and mathematicians calculate the total number of humans that have ever lived. —Andrea Gawrylewski, Chief Newsletter Editor TODAY’S NEWS Dmytro Varavin/iStock/Getty Images How many people have ever lived on Earth? Mathematicians have used different techniques to estimate. | 6 min read If you liked the “unknot” puzzles yesterday, here are more knotty mysteries that have emerged in the burgeoning field of knot theory. | 5 min read Jane Goodall challenged what it meant to be a scientist in three big ways. | 3 min read Adidas officially unveiled the 2026 FIFA World Cup’s new Trionda ball. Here’s the mathematics behind the Trionda ball’s design. | 5 min read More News TOP STORIES Boundaries Breached In a new report, researchers examined nine geophysical limits that make up a sort of planetary life-support system; staying within these limits, they say, is the best hope for maintaining the climatic conditions humans and other organisms on Earth have adapted to. As of 2025, humans have pushed Earth past another of these planetary boundaries: Levels of ocean acidification have exceeded a critical threshold, becoming the seventh out of nine boundaries crossed. How it works: Carbon dioxide concentrations reached a record global high of 422.7 parts per million (ppm) last year. Much of that carbon dioxide gets absorbed by the ocean, increasing its acidity, which can have profound impacts on marine ecosystems. At low enough pH levels, corals and shells can begin to dissolve. These effects could destabilize entire ecosystems and devastate many commercially valuable species, such as oysters. What the experts say: “The movement we’re seeing is absolutely headed in the wrong direction. The ocean is becoming more acidic, oxygen levels are dropping, and marine heatwaves are increasing. This is ramping up pressure on a system vital to stabilize conditions on planet Earth,” Levke Caesar, co-lead of PIK’s Planetary Boundaries Science Lab, said in the new evaluation’s press statement. Amanda Montañez; Source: “Planetary Health Check 2025: A Scientific Assessment of the State of the Planet,” Planetary Boundaries Science, Potsdam Institute for Climate Impact Research (data). The most distant galaxies in this deep field image from the James Webb Space Telescope appear as small, faint dots. ESA/Webb, NASA & CSA, G. Östlin, P. G. Perez-Gonzalez, J. Melinder, the JADES Collaboration, M. Zamani (ESA/Webb), CC BY 4.0 INT Faster-Than-Light Galaxies Nothing can move quicker through space than the speed of light. The distinciton is important. The universe—space itself— is constantly expanding, but the rate of expansion grows the farther away from us you measure. A galaxy one megaparsec from us (about 3.26 million light-years) will be receding at 70 km/sec. A galaxy two megaparsecs away will be moving twice as fast, or at 140 km/sec, and so on. So at a certain point, a galaxy will be moving away from us at the speed of light. Calculations show that this distance, which is called the Hubble sphere, is about 14 billion light years away. Anything farther away would be moving faster than light from our perspective. How it works: Though these galaxies are moving quicker from us than the speed of light, they are not moving through space faster than light. They are moving with it, writes Phil Plait in his weekly column. He gives an analogy: “Imagine a boat on the ocean that can move across the water at 20 km/hour. If the boat is headed away from you, that’s how fast you’ll see it moving. But now imagine the boat’s in a current moving at 30 km/hour away from you. You’d now measure the boat moving at 50 km/hour, even though the speed of the boat relative to the water is only 20. To be clear, this is only an analogy and shouldn’t be taken too far. But it helps to picture how this works.” What this means: The cosmos was born approximately 13.8 billion years ago. Hundreds of millions of years later, galaxies formed. Light from distant galaxies has taken about 12 billion years to reach us, but over that time, the universe has expanded. Technically, the light has traveled much farther than 12-billion-light-years to reach us. By the time it reaches us, the galaxy is more like 23-billion light-years away. —Andrea Tamayo, Newsletter Writer

Explore the universe and feel the awe of science. Subscribe to Scientific American with a special discount for Today in Science readers. PLAY NOW See how well you read Scientific American this week by taking today’s quiz! Also, try to solve Spellements and our killer version of Sudoku. This week, Bruce F. and Amir C. both found the word modally in the Spellements puzzle. It’s an adverb relating to modality. Excellent word. More Games MOST POPULAR STORIES OF THE WEEK Marsh Will-o’-the-Wisps Sparked by Strange Chemistry | 3 min read Smallmouth Bass Evolve to Evade Electric Culling in Adirondack Lake | 2 min read People Are More Likely to Cheat When They Use AI | 4 min read Thanks for reading Today in Science this week. We’re barreling past troubling markers of the planet’s health, and the stakes can feel overwhelming. But it gives me real comfort to be part of this community of science-minded readers—curious, informed, and unwilling to look away. If change is going to come, I suspect it will begin with people like you. Wishing you a restful weekend. You can always email me: newsletters@sciam.com. See you Monday. —Andrea Gawrylewski, Chief Newsletter Editor With contributions by Andrea Tamayo

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