Popular Science

Researchers have long assumed that the timing of American black bear (Ursus americanus) annual hibernation mostly depends on temperature. However, new research indicates that how the bears know it’s time to hibernate might be more complicated than they once thought. 

A team from Virginia Tech investigated how temperature and daylight hours interact to influence the species’ hibernation behavior. To do so, the team followed the activity of four wild, pregnant female bears throughout various hibernation stages in over 22,000 hours of video footage from the university’s Black Bear Research Center. 

They categorized 45 behaviors and associated them with environmental triggers like temperature and photoperiod (day length), plus physiological changes in the course of hibernation. “To our knowledge, no studies have investigated the interplay between photoperiod and temperature in bear hibernation ecology,” they wrote in a study published in the journal Proceedings of the Royal Society B: Biological Sciences.

According to their findings, both temperature and day length are significant and interacting contributors to bear activity in relation to hibernation, especially during important phases like pre-hibernation feeding and den emergence. At the beginning of hibernation, only temperature shaped the bears’ behavior, but activity in other periods was significantly prompted by the effects of temperature and a day’s amount of sunlight together. 

A black bear is caught on a trail cam walking in the forest near Blacksburg. Image: Photo courtesy of Brogan Holcombe.

While temperature primarily drives the black bears’ hibernation timing, there is a more complicated dynamic between environmental signals. And shifting climate patterns could disturb this relationship. Climate change could pull apart the link between the amount of sunlight in a day and temperature, since daylight is constant and temperature isn’t. Decouplings of this sort could change hibernation timing and trigger chain reactions within the ecosystem, in addition to bringing about more human–wildlife interactions.

“Understanding relationships between physiological and environmental cues during hibernation is important for predicting behaviours in a changing climate,” writes the team, led by graduate student Brogan Holcombe, who studies black bears at the Virginia Polytechnic Institute and State University. “We also highlight the potential for a mismatch between physiology and environmental cues in areas projected to experience increased temperatures under a changing climate.”

As with most things in nature, the more scientists know about a species, the better equipped they are to protect it. As such, this study could help wildlife managers predict changes in black bear behavior and prepare for the future. 

The post Virginia scientists discover the cues black bears use for hibernation appeared first on Popular Science.

For the last five months, I’ve had a daily date with a little green owl. It cheers me on when I finish a language lesson and sends passive-aggressive reminders when I put it off. 

A few months in, I was thrilled to realize I could follow bits of a German conversation I happened to overhear. But I still wondered: If I keep using this app, will I actually be able to understand entire conversations and express myself clearly? So I asked some experts.

What language apps do well

Apps like Duolingo and Babbel, which break a language into a sequence of bite-size, gamified lessons, have several strengths, says Dr. Luke Plonsky, a professor of applied linguistics at Northern Arizona University. They combine audio, written text, and visuals, which helps learners connect how new words look, sound, and what they mean. 

They also enable something called “spaced practice”—going back to what you’ve learned several times over a longer period. Several studies show this leads to better memory of the new material than cramming. 

For example, if students spend 30 minutes learning vocabulary, they remember the words longer if they break that into three 10‑minute sessions spread over several days or weeks, instead of doing all 30 minutes at once.

In fact, “language apps tend to do a good job with vocabulary, short phrases, and other concrete material that benefits from repetition and memorization,” says Dr. Gillian Lord, a professor of Hispanic linguistics at the University of Florida.

Researchers at Duolingo published a peer‑reviewed study claiming that finishing certain parts of their French and Spanish courses gives learners reading and listening skills similar to those of students who have taken four university semesters—and in much less time. But it’s important to note this study didn’t compare speaking or writing ability.

On the practical side, apps are often free and “very convenient since they’re on our phones and can be accessed 24/7,” Plonsky says. 

Another strong point is their emotional appeal. “Duolingo’s character Lily [a teenager known for her sarcastic comments] is funny. The Owl is charming. The sounds and haptics are pleasing and rewarding. And the apps are gamified by features like streaks and hearts, which motivate us to keep going,” Plonsky explains. Starting a new language can feel intimidating, and—by making the process more playful—these apps lower the barrier to entry, says Lord. 

The Duolingo owl can help you learn Spanish, but it can also dance. Video: oy nambir oscar tuş, @duolingo

Dr. Daniel Isbell, an associate professor in the Department of Second Language Studies at the University of Hawaiʻi at Mānoa, points out how these apps help make learning a habit by sending reminders and using gamified elements like experience points (also known as XP, points you earn when you finish a lesson) or streaks (number of days in a row in which you’ve completed lessons). That consistency matters because language learning is “more of a marathon than a sprint,” and it can take several thousand hours to reach high proficiency, he says.

Where the apps fall short

The bad news for language app learners like me is that an app alone may not equip you with the skills you need for real-life communication. 

“Even when they incorporate speaking practice, it is usually highly controlled—repeat this phrase, pronounce this word, give the expected answer,” says Lord. “Someone can perform quite successfully in an app and still be entirely unprepared for a real, unscripted conversation!” 

Live human communication involves “interpreting meaning in real time, responding to unpredictability, managing misunderstanding, and adjusting to another person—a level of complexity that apps just can’t replicate,” she says.

What this means, Isbell explains, is that an app can help you “get the basics of the language under your belt,” “enough to read some subway signs and ask for directions,” but not to use the language comfortably at school or work.

Plonsky points out another limitation: Apps often avoid clear explanations of grammar, even though many adults “actually want to know what’s going on structurally!” 

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Culture, which is integral because “language always exists within a varied and living human context,” is often treated “too superficially,” says Lord. When it does appear, “it is often presented as though it were fixed and uniform, reduced to a handful of customs, holidays, or tourist-facing facts.”

Another big issue is dropout. Despite reminders and gamified elements, studies show many language app users quit before achieving fluency. For example, a 2019 study found that 64 percent of people had stopped using the app after four months, and 87 percent had stopped after a year. 

“So for every 1,000-day streak you see on social media, there are thousands and thousands of people who stop using their language learning app within a month, which is a big problem,” Isbell says. Language classes, meanwhile, “create some social expectations to show up and participate,” he notes.

Expert tips for learning a new language

So where does that leave me? “Sure, use the apps!” Plonsky says. “They’re probably the most efficient way to go, at least in the early stages. And they’re fun.” Lord agrees that apps are “fine as a starting point,” and Isbell recommends using them to build more practice and exposure into your daily routine.

But you should also seek out other opportunities to use the language. Ideally, learners immerse themselves where the language is spoken, Lord says, but if that’s not possible, they should seek “the most interactive option available”—“very often that means taking a class, whether in person or online.”

It also helps to expose yourself to films, TV, podcasts, and music in your target language to “get used to the sounds of the language, the rhythms of interaction, and the cultural norms that shape communication,” she adds. 

For example, with Korean, “you can get some of the basics from an app like Duolingo,” but you should also watch K-dramas and focus more on listening than reading subtitles, Isbell says.

So my plan is to keep the owl happy and maintain my streak—but also to sign up for a class where I can put my new vocabulary into practice with real people. Gulp.

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

The post Can apps really make you fluent in another language? appeared first on Popular Science.

Today at 7:26 a.m. EDT, the Nancy Grace Roman Space Telescope officially launched aboard a SpaceX Falcon Heavy from NASA’s Kennedy Space Center near Cape Canaveral, Florida. The Falcon Heavy’s 27 Merlin engines generated over 5 million pounds of thrust, and pushed the rocket through the atmosphere. It got it’s “first taste of space” about four minutes after liftoff.

The Nancy Grace Roman Space Telescope shortly after launch. Image: NASA

Roman is now en route to the second Lagrange point (L2), roughly 932,000 miles “behind” Earth as viewed from the sun. Once it reaches L2, the new space telescope will be about four times farther from Earth than the moon.

Ahead of the launch, NASA also announced the Adopt a Pixel campaign, where users can claim a pixel on one of Roman’s first images. Users will be assigned a pixel number that they can look up and receive a printable digital certificate.

Teams inside the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center in Florida encapsulate the agency’s Nancy Grace Roman Space Telescope within the payload fairing on Friday, August 21, 2026, ahead of mating to a SpaceX Falcon Heavy rocket. Encapsulation shields the spacecraft during rollout, ascent, and the early phases of flight. Image: Kennedy Space Center / NASA What is Roman’s mission?

First announced in 2020, the Roman Space Telescope arrives after years of development—as well as a close brush with cancellation in 2025. Astronomers estimate the Roman Space Telescope will measure light from as many as one billion galaxies while also conducting the first complete statistical census of planetary systems in the Milky Way. The discoveries made over the course of its five-year mission are expected to help answer some of the most persistent questions about infrared astrophysics, exoplanets, and dark matter. If all goes well, NASA may even extend the mission for an additional five years.

NASA’s Nancy Grace Roman Space Telescope will survey vast swaths of sky during its five-year primary mission. During that time, scientists expect it to see an incredible number of new objects, including stars, galaxies, black holes and planets outside our solar system, known as exoplanets. This infographic previews some of the discoveries scientists anticipate from Roman’s data deluge. Image: NASA’s Goddard Space Flight Center/ Scott Wiessinger (eMITS)/Ashley Balzer (eMITS)/Julia Shepherd (Intern)/

Scientists will also pair Roman’s infrared data with visible-light observations taken from the ground-based Vera C. Rubin Observatory, a National Science Foundation–Department of Energy collaboration.

What’s onboard?

Roman’s equipment includes a massive, 300.8 megapixel camera known as the Wide Field Instrument (WFI), as well as a system of prisms, self-flexing mirrors, masks, and detectors collectively known as a Coronagraph. This addition will help block the glare of distant stars in order to better focus on their orbiting plants. 

The telescope’s nearly eight-foot-wide mirror and accompanying instruments will provide it with a field of view about 100 times wider than Hubble. While the primary mirror is about the same size as Hubble’s, design advancements have lightened the overall weight by about 80 percent.

NASA’s Nancy Grace Roman Space Telescope pictured on Friday, August 7, 2026, after engineers and technicians working inside the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center in Florida had carefully mated the observatory to its payload adapter and a strut payload attach fitting, a specialized piece of hardware designed for large, heavy loads. This allows the team to secure the payload to the second stage on SpaceX’s Falcon Heavy rocket. Image: Kennedy Space Center / NASA.

It also carries 1.35 million names aboard on a commemorative memory card. These names were submitted by people all around the world, including astronauts from Artemis II and Artemis III. April’s Artemis II also has a special memory card with names aboard.

Who was Nancy Grace Roman?

The space telescope is named in honor of Nancy Grace Roman (1925-2018), NASA’s first chief astronomer and a pioneering advocate for the development of orbital observatories. Widely known as the Mother of Hubble, Roman was instrumental in securing funding support for the once-controversial project.

Nancy Grace Roman, shown here at NASA’s Goddard Space Flight Center in approximately 1972, was the first female executive and the first Chief of Astronomy at NASA. Image: NASA

“Hubble has brought astronomy into everyday life in a much more general way than it was before. The fact that it exists is something I’m proud of,” she said.

Roman’s love of astronomy began when she was a child. She had already formed an astronomy club for her classmates by the age of 11 in Reno, Nevada, and later graduated high school a year early while through an accelerated program in Baltimore, Maryland. She faced numerous obstacles as one of the first women in the field of astronomy, at one point even leaving her position at the University of Chicago after it became clear she wouldn’t receive tenure due to her gender. Her dedication to making the Hubble Space Telescope a reality ultimately led to the identification of dark matter, which she famously considered the program’s most interesting discovery.

Nancy Grace Roman stands next to a scale model of the Hubble Space Telescope outside the Hubble control center at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Roman is known as the “Mother of Hubble.” Image: NASA When should we see Roman’s first images?

We should receive the first images in early 2027. Over the next three months, the NASA team will perform an orchestrated series of deployments, calibrations, and tests before Roman reaches its final orbit. Roman has a primary mission lifetime of five years and is designed to support an additional five years.

The post NASA’s Nancy Grace Roman space telescope launches appeared first on Popular Science.

Mountain yellow-legged frogs used to be the kings of the mountain. Specifically, the Sierra Nevada mountains, where they were once the region’s most common amphibians only. But their reign has since plummeted dramatically. Now 92 percent of their historic range is void of the colorful animal.

“These frogs used to be quite abundant. In the Sierra Nevada mountains, there are reports of showers of frogs jumping as scientists walked along a lake bank, and even of it being difficult to take a step without landing on a frog,” Tali Hammond, a recovery ecology researcher at the San Diego Zoo Wildlife Alliance, tells Popular Science. “It’s hard to say when, exactly, this was last true. We know that throughout the species range, populations have been declining since the late 1960s/early 1970s.”

There are two species of mountain yellow-legged frogs: Rana muscosa, the southern mountain yellow-legged frog, and Rana sierrae, the Sierra Nevada mountain yellow-legged frog. Both species are classified as Endangered by the IUCN Red List. 

Specifically, experts estimate that fewer than 200 adult southern mountain yellow-legged frogs remain in their native habitats, according to the San Diego Zoo Wildlife Alliance. The species is threatened by common menaces such as disease, introduced predators, wildfire, and drought. But the team at the San Diego Zoo Wildlife Alliance is on a mission to change all that with shocking numbers of their own, though not currently in the Sierra Nevadas.

This year, they reintroduced over 3,000 southern mountain yellow-legged frogs and tadpoles into the San Bernardino and San Jacinto mountains in California. Overall, they reintroduced more than 10,000 of the little amphibians into these high-elevation mountain habitats. 

A mountain yellow-legged frog leaps into a new life. Image: San Diego Zoo Wildlife Alliance.
Ken Bohn

But the amphibians aren’t left completely on their own. Conservation teams are monitoring the frogs to keep an eye on their health, survival, and success. One of this year’s reintroduction sites is Bluff Lake in the Big Bear area (not far from a particularly famous bald eagle nest), where experts waded into the water and gently encouraged the frogs to hop out of their clear containers. 

San Diego Zoo Wildlife Alliance and others have been protecting the species for 20 years, and 2026’s efforts are part of a decades-long mission to restore the amphibian’s populations across its historic range. Returning these ruling frogs to their kingdom, if you will. 

“What began as a rescue effort has grown into a comprehensive conservation program focused on breeding, genetic diversity, disease management, reproductive research and reintroduction,” the zoo wrote in an e-mailed statement. 

The post Over 10,000 endangered mountain yellow-legged frogs are taking California by storm appeared first on Popular Science.

There are many ways to scour the stars for intelligent life. You can search for radio signatures whose repetitions suggest intentional design, or examine a planet that orbits its star in a so-called Goldilocks Zone conducive for habitation. One of the wildest (but still hypothetically plausible) scenarios involves what’s known as a Dyson sphere.

What is a Dyson sphere?

Named after physicist Freeman Dyson, the idea hinges on an alien civilization so advanced that they invent a method to directly harness the energy of an entire star. Extraterrestrials could theoretically accomplish this feat in a number of ways, but the simplest approach would likely entail encasing a stellar object with orbital installations that absorb solar radiation, convert it into usable energy, and then re-emit that power back to the Dyson sphere’s engineers.

While Dyson himself once described his original 1960 paper as “a little joke,” he later conceded that the underlying technical details are “correct and uncontroversial.” Despite the joke, many researchers today agree, and argue that searching for Dyson spheres is one of the easiest ways to identify extraterrestrial life.

Enter the Webb

Unfortunately, an ongoing cosmic survey called Project Hephaistos at Sweden’s Uppsala University has once again crossed off multiple candidates from their list of suspects. According to their findings detailed in two soon-to-be published studies, a pair of faint, distant red dwarf stars aren’t surrounded by high-tech alien energy harvesters. Although disappointing, the findings highlight the ongoing versatility of one of astronomy’s most impressive tools—the James Webb Space Telescope (JWST or Webb).

Astronomers theorize that any functioning Dyson sphere will generate a technosignature in the form of waste heat that’s emitted as excess mid-infrared radiation. Researchers including Uppsala University astrophysicist Andreas Korn previously flagged multiple dwarf stars with “unusual infrared properties that seem[ed] to resemble those expected for Dyson spheres.” These were selected while employing the European Space Agency’s Gaia satellite and NASA’s Wide-field Infrared Survey Explorer (WISE), with the candidates exhibiting unexpectedly low optical fluxes and higher infrared fluxes. The subject pool was vast—around 1 million stars located within around 1,000 light-years of Earth.

“This is the signature that we were looking for: a star that is a little bit too faint in the optical and has substantial amounts of waste heat in the infrared,” Korn recently explained.

The team ultimately determined their most promising options were two faint M-dwarf stars that are invisible to the naked eye here on Earth and about a few billion years old each. Researchers then used the JWST to gain a more focused look at each star. Sadly, neither ended up revealing themselves as an elusive Dyson sphere. In actuality, they are pretty standard M dwarfs whose energy is jumbled by background galaxies.

“WISE gives us just a coarse image, and that’s why the photons from the background galaxy and the M dwarfs were blended together so we couldn’t tell them apart,” explained Korn. “But with Webb, we can tell the two apart and conduct separate analyses of either the galaxy or the foreground M dwarf.”

This isn’t the first time Project Hephaistos has encountered similar issues. As time goes on, it appears that many of their Dyson sphere candidates are obscured by background galaxies. That may not always be the case, however. Multiple proposed mid-infrared telescopes—including the Giant Magellan Telescope—are scheduled to arrive by the 2030s. Until then, the hunt for Dyson spheres continues.

The post Sorry, aliens didn’t build Dyson spheres around these dwarf stars appeared first on Popular Science.

The votes are in, and a German shorthaired pointer named Bolt is officially the winner of the  Transportation Security Administration’s (TSA) Cutest Canine Contest for 2026. The three-year-old pooch works at Dallas Fort Worth International Airport (DFW) in Texas and is the third German shorthaired pointer to win the contest in the last four years

The nationwide contest takes place on social media, where the traveling public  can vote for the agency’s cutest dog. TSA canine handlers from across the country initially nominated 85 dogs before an initial round of employee voting, narrowed the field to the final four canines.

“Canines are an essential part of our team at TSA,” Deputy Administrator Ha Nguyen McNeill said in a statement. “As cute as Bolt and our other canines are, the work they do is vital for TSA’s national security mission.”

Dogs like Bolt help the TSA sniff out explosives. Image: TSA.

Bolt is the third German shorthaired pointer to win the contest in the last four years. According to the American Kennel Club, German shorthaired pointers are medium-sized dogs who thrive on vigorous exercise, positive training, and a lot of love. While Bolt does not have too many spots on his coat, many German shorthaired pointers have patches on their coats. 

Bolt’s handler, Daphne Wang, called her canine partner an intense worker, with quite the personality. 

“I am ecstatic for Bolt,” Wang said. “He is such a character and a hard-working little guy. He absolutely loves his job and coming to work. I am so happy he gets to show the world his quirky personality. It’s definitely an adventure working with Bolt every day. There is nothing ordinary about him. He works hard and plays even harder. He is always in working mode, even at home. He is never short on energy and is always 1,000% excited to go to work.”

The three runners ups are:

• Ember: A four-year-old Labrador retriever from Orlando International Airport in Florida. TSA Explosives Detection Canine Handler Oscar Urdininea began working with Ember after retiring his previous working canine, Bona. Urdininea said Ember and Bona love playing fetch or lying on the couch next to each other. Ember enjoys coming to work, searching all areas in and around the airport and loves to eat steak chunks and play with her squeaky bone.

• Epic: Also a four-year-old Labrador retriever, Ember works at Pittsburgh International Airport in Pennsylvania, which is the home of the 2025 TSA Cutest Canine winner, Steeler. Epic has been working for about two years. His explosives detection canine handler, Devon Flaig, says his favorite food is chicken jerky and his favorite reward is playing with a Gappay ball. 

• Xaro: A nine-year-old German shepherd from St. Louis Lambert International Airport in Missouri, Xaro is planning on retiring by the end of the year. Handler Raymond Wu said Xaro loves playing tug with a ball on a rope and his new favorite treats are Three Dog Bakery Lick’n Crunch golden & peanut butter sandwich cookies. After a long day of work at the airport, Xaro enjoys napping in the sun with his head on a pillow. 

The TSA’s explosives detection canine teams weave through large groups of moving people in the airport to detect the source of an explosive’s odor. The teams train regularly, and the human handlers learn to read subtle changes in dog’s behavior, including when they smell the scent of an explosive. If a canine alerts its handler that an explosive odor is present, the handler follows an established procedure. 

As tempting as it is to pet them, the dogs and handlers are hard at work when on duty and must not be touched. 

Later this year, the public will be able to download the free 2027 TSA Canine Calendar. The calendar will feature 12 contestants from TSA’s 2026 Cutest Canine Contest, including Bolt. The 2026 Canine Calendar is still available.

The post Say hello to the TSA’s Cutest Canine of 2026 appeared first on Popular Science.

The weather forecast did not inspire confidence for Allied forces ahead of June 6, 1944. The thick clouds blanketing much of France and the English Channel made aerial reconnaissance even more dangerous than anticipated, while stormy conditions complicated the naval advance towards Normandy Beach. But despite the challenges, calling off D-Day remained unthinkable.

“Troops set off into a sky that was still breaking up after days of storms into a narrow window of better weather,” University of Reading meteorologist Ed Hawkins explained in a statement. “A day earlier, or a few hours either way, and the weather could have stopped the invasion in its tracks, and changed the outcome of the war.”

Hawkins recently collaborated with researchers at the European Center for Medium-Range Weather Forecasting to visually illustrate the precarity of one of history’s most consequential military invasions. To do this, the team amassed archival weather readings and then entered the data into a synthesis modeling method known as reanalysis. This approach is particularly useful for historical studies, because it is designed to account for observational biases in meteorological instruments used in the past, while also addressing any informational gaps.

Reanalysis allowed meteorologists to accurately recreate the cloud cover across Britain, the English Channel, and France on June 6, 1944. Credit: University of Reading

The resultant satellite images reveal that June 6, 1944, was a particularly gray day across Great Britain and most of the English Channel. At the same time, small patches over northern France and southern England indicate skies were at least beginning to clear earlier in the day. This aligns with archival weather reports from Normandy on the morning of the invasion, which reference a mostly sunny sky and north-westerly winds. Although not ideal, it was a major improvement over the previous day’s stormy conditions.

Slightly more favorable weather made all the difference. Without meteorologist Captain James Stagg convincing General Eisenhower to postpone the invasion by one day, troops would have experienced a far more dangerous crossing that put them at even more of a disadvantage against entrenched Nazi forces.

“Images like this help us understand what troops, sailors and pilots actually faced that day, in a way written reports alone cannot,” said Hawkins. “They show just how narrow the margin was between success and failure, and how much was riding on a small break in the cloud.”

The post Forecasters recreate the weather that made D-Day possible appeared first on Popular Science.

What does it take to swim up to the world’s largest fish and stick a monitoring tag on it? The patience of a saint, the flexibility of a bendy straw, and the endurance of an Olympic swimmer.  

“Even though the shark looks like it’s swimming slowly, it’s definitely a lot faster than you are,” marine biologist and ace whale shark tagger Jaida Elcock, tells Popular Science. “Even if you have the best fins, you’ve got to have great endurance. It’s like holding your breath after sprinting.”

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Elcock is currently working on her PhD through a joint program between MIT and Woods Hole Oceanographic Institution (WHOI). She is studying the movement ecology and habitat use of two of the largest fish in the world, basking sharks (Cetorhinus maximus) and whale sharks (Rhincodon typus).

Elcock tagged this particular whale shark about 100 miles off the coast of New England, in the northeast canyon and seamounts region in northwest Atlantic. This area is a bevy of biodiversity, with plenty of plankton. 

“There are whale shark aggregations all over the place. The Philippines, Mexico, Australia, tropical places like that. A lot of these aggregations are also often young individuals, subadult individuals, juveniles,” Elcock says. “Out in the [northeast] canyons, we’re seeing large adults. They are definitely of reproduction age and size, and that’s not really something that we’re able to reliably find very often.”

Unlike other tagging procedures, scientists can’t use baited hooks to quickly catch the shark, tag it, and release it, with whale sharks. These fish that can grow up to 60-feet-long are simply too big and are filter feeders, so they can’t take bait on a line the way a white shark or tiger shark can. To find sharks, it takes support from both land- and ocean-based crew.

“We get on a boat and we wait for a spotter pilot to come and tell us that there’s a shark at these coordinates,” says Elcock. “Once we get to the shark, we have to hope that it doesn’t just dive.”

Once they are near the whale shark, two people get in the water. One has a camera to take pictures or video to help identify whale sharks by the markings on their bodies. The other swims ready with the tag that will collect data on water temperature, the whale’s travel patterns, how deep its diving, and more. According to Elcock, the tracker looks like “a big bobby pin that you have to pry open with your hands and pull onto the shark’s fin.”

Whale shark tags will pop off on their own and have a radio transmitter so the team can retrieve them. Image: Jaida Elcock (@sofishtication_) / Woods Hole Oceanographic Institution

Once tagged, the big fish swims on its way and the tag will eventually pop off. A built in radio transmitter helps the team find its location, scoop it up, and analyze the data. Elcock is currently working on the data collected from last year’s tagging to see what they can tell us about why they are gathering in the northwestern Atlantic Ocean and what they are doing there. 

While swimming this far out in the ocean next to one of the planet’s most majestic creatures is something most people will never experience, Elcock says it feels particularly surreal.

“I grew up in the desert, so being in a place where it’s only water, and I can’t see land is a very odd thing for me, even now,” she says. “There’s just a level of excitement. There are nerves about what if a tag doesn’t stay on, rather than what if some other animal pops up out of nowhere. We’ve had situations where we’re tagging a whale shark, we see a hammerhead just like hanging out over in the corner. So there’s a lot of life out there to see.”

The post How do you tag the world’s biggest fish? Fins and flexibility. appeared first on Popular Science.

Japan is synonymous with vending machines. The island-nation has vending machines for everything: fresh flowers, bowls of hot ramen, edible grasshoppers, umbrellas. Want a fresh farm egg or flower bouquet? There’s a vending machine for that! 

Japan is home to over 2.6 million vending machines: meaning that with approximately 122 million residents, there’s approximately one vending machine for every 45 to 50 people. 

But it turns out these contraptions of convenience had quite a long history before they became popular in Japan. It’s a story that left us wondering: Just how did vending machines become so ubiquitous in this Asian country, and what’s the science behind how they work? 

To get some answers, Popular Science turned to David Widjaja, former vending machine employee and current owner of Japantogo LLC, an Ishikawa-based exporter of Japanese vending machines, to give us the inside scoop. 

A brief history of vending machines

Famous Greek engineer and inventor Hero of Alexandria created the world’s first known vending machine in ancient Egypt during the first century AD. Hero utilized the powers of physics to dispense holy waters in temples. Hero’s dispenser used a simple counterweight lever system (picture the scales of justice, with two hanging pans held by a horizontal beam that adjusts its position, depending on which pan is heavier). When someone dropped a coin into the contraption, the coin would land on one of the scale’s pans. The weight of the coin would then trigger a valve and let out a flow of holy water. 

Famous Greek engineer and inventor Hero of Alexandria created the world’s first known vending machine in ancient Egypt to dispense holy water. Image: Universal History Archive / Contributor / Getty Images / Universal History Archive

Despite its ingenuity, the concept of vending dispensers pretty much disappeared until the late 19th century. That’s when coin-operated machines filled with postcards, envelopes, and notepaper began popping up on railway platforms throughout London for travelers on-the-go. 

Soon, the device made its way across the pond. By 1888, the Thomas Adams Gum Company was placing vending machines stocked with Tutti-Frutti chewing gum all along New York City’s transit lines. Before long, vending machines offered everything from cartons of milk to refrigerated sandwiches. 

Still, it wasn’t until after World War II that vending machines became a staple of Japanese culture. It happened during the country’s rapid postwar economic recovery. 

“They’re very convenient,” says Widjaja. “Japanese people are often in a rush, and we want something on the go. If you go into the store, it can cost you four or five minutes of waiting.” With vending machines, you can get what you need immediately. 

How do vending machines work?

Vending machines rely on an embedded computer system, which is a specialized computer system designed for a specific use. In this case, the embedded computer consists of a microcontroller (a tiny, self-contained computer), sensors, and actuators (the gear motors and pusher tracks that open access hatches and get that soda to fall). 

“Actually, vending machines are simple,” says Widjaja. The microcontroller acts as the machine’s “brain.” It receives user input (e.g. when you push your numbered selection), validates payment, and sends commands to the dispensing motors—the rotary power sources for each individual item. 

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Payment validation

Once you put coins or paper money into a vending machine, the machine uses electromagnetic sensors to verify that the payment is legit. These sensors figure out which kinds of coins are inserted—and whether or not they’re authentic—by using electric and magnetic fields to determine a coin’s metal makeup. Basically, each metal alloy (e.g. nickel, iron, etc) produces a specific effect on the magnetic field. 

For example, when cheap iron passes through the machine’s magnetic lines it becomes temporarily magnetized. On the other hand, pure aluminum can pass through these same magnetic lines with little effect. The machine’s microcontroller will then instantly compare these results against a pre-programmed database of real coins, determining  whether the coin inserted is real or fake. 

At the same time, optical sensors measure the coin’s diameter, thickness, and speed. When a coin rolls down the vending machine’s chute, it casts a shadow on a light sensor. The microcontroller times exactly how long the light remains blocked. This allows it to calculate the coin’s precise diameter. Another light sensor measures how fast the coin is traveling, which helps the microcontroller confirm if it is moving abnormally fast or slow. If it’s one or the other, the coin is likely fake. The machine will then reject it.

For paper money, optical sensors use infrared and UV light sensors to read hidden security markings and magnetic ink (banknotes are printed with special magnetic inks containing iron oxide). 

If you’re using a credit card, the machine will send encrypted data through an attached telemetry gateway device—a hardware unit that collects data from the machine’s sensors—straight to a banking network. This allows the microcontroller to instantly verify if your payment is legitimate. 

Dispensing 

After your payment is accepted and you’ve punched in the code for your desired soda or bag of chips, the microcontroller switches modes. This tiny brain then sends a signal to the dispensing motor assigned to the object that you’re purchasing. 

Some machines use spiral coils that rotate 360 degrees and push a bag forward until it tips over the edge of the shelf. Others use robotic elevator arms or picker mechanisms that rise to a specific shelf, secure a drink, and gently lower it to prevent it from exploding. 

There are also machines that utilize a traditional gravity and drop system, in which the selected product simply slides off a slanted shelf and falls directly into the retrieval bin. 

In Japan, some vending machines even dispense bowls of hot ramen. Video: Ramen Noodles Vending Machine in Tokyo, TabiEats How Japanese vending machines differ

Many vending machines also include small refrigeration units to keep things cold, or internal built-in microwaves and instant heaters (long, narrow internal pipes that heat up to 2,000 Watts within seconds) for warm drinks like coffee and tea. 

However, dual-temperature machines that disperse both hot and cold products from the same unit are rare in the United States. That’s not the case in Japan, where Widjaja says vending machines are all about efficiency. “You can sell cold drinks during summer, and hot coffee during winter, all from one machine.” 

These specialized units feature two separate, heavily insulated zones: one for hot beverages and one for cold beverages. Many modern dual-temperature vending machines also feature an innovative heat-pump system—one that recycles the thermal energy generated from the machine’s cooler side and pipes it into its warm section. This helps to significantly reduce the machine’s overall energy consumption. 

Because Japan is prone to natural disasters, many of its vending machines are also designed to be “earthquake proof.” Their heavy parts, such as thick metal bases and compressor pumps that are actively circulating refrigeration gases to keep products cold, are built into the machine’s lower portion. 

“We call this area the ‘basement,’” says Widjaja. The bottom-lying weight helps to steady the machines in earthquake zones. “In Japan, everything is about safety.”

Another feature: free-dispense activation. “We call it ‘free vending,’” says Widjaja. Say there’s a large earthquake in Tokyo. These machines may have built-in sensors that detect heavy shaking, or are programmed to receive signals from local city authorities. In either case, “a router inside automatically switches to ‘free mode.’ The machine will then disperse free drinks so that everyone can have a beverage.” 

Although the number of vending machines in Japan has recently been decreasing, in a country with very low crime and millions of pedestrians on foot they still make sense. 

“Japanese people like a lot of options,” says Widjaja. “Vending machines have these options, and you don’t have to wait in line!”

In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.

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Less than five years after the revolutionary James Webb Space Telescope’s (JWST or Webb) debut, NASA is heading back to the launch pad to deploy another world-class space observatory—the Nancy Grace Roman Space Telescope. Called Roman for short, the space telescope will hunt dark matter, dark energy and exoplanets, as well as providing an unprecedented view of the cosmos to all sorts of astrophysicists.

With Webb and the venerable Hubble Space Telescope continuing to gather ever more observations, it’s easy to wonder what another mission will add to the mix. But scientists in the know can’t wait for Roman to really get to work early next year. Its unique capabilities will complement Hubble and Webb while creating its own hugely important legacy—even if people aren’t quite as familiar with it yet. 

“Roman is kind of like a quiet underdog,” Elisa Quintana, an astrophysicist at NASA’s Goddard Space Flight Telescope who previously served as Roman’s deputy project scientist for communications, tells Popular Science. “All of the data they’re collecting is going to be a goldmine for many, many decades.”

This Roman Simulated Image (1/140th Roman field of view) of the center of our galaxy. Image: NASA Scientific Visualization Studio Roman’s mission

The mission has three massive research goals: hunt down the subtle signatures of dark matter and dark energy, identify tens of thousands of new exoplanets, and collect a flood of general astrophysics observations—data on hundreds of black holes, billions of galaxies and 100 billion stars. Named for NASA’s first chief of astronomy, the tour-bus-sized spacecraft will accomplish all that with just one instrument, although a second, experimental instrument is riding along to attempt to spot alien planets similar to our own Jupiter. 

To tackle its packed agenda, Roman will pan across the skies in a carefully choreographed dance to which it is uniquely tailored.

“It is a big survey machine, but also at high resolution. “Usually, you have to pick one or the other,” Sabrina Stierwalt, an astrophysicist at Occidental College in California, tells Popular Science. Stierwalt is also the co-chair of the Roman Science User Panel, which is a liasion between the mission team and the global science community. 

Roman’s focus on surveying is built into its very fabric in a way that NASA’s existing flagship telescopes can’t match. 

“It’s not just that we have a field of view that’s much larger than Hubble and Webb,” Julie McEnery, an astrophysicist at NASA’s Goddard Space Flight Center in Maryland and senior project scientist for Roman, explains to Popular Science. 

The mirror—the heart of any telescope—and the spacecraft as a whole are lighter than both Hubble and JWST. 

“We have an observatory that can move nimbly, it can stop on a dime,” McEnery says.

Over the course of several hours, technicians meticulously connected the inner and outer segments of NASA’s Nancy Grace Roman Space Telescope. Image: NASA/Jolearra Tshiteya. Jolearra Tshiteya Roman vs. Webb

Webb is a prime example of the other side of that talent tradeoff, with Webb prioritizing a truly massive mirror that offers super-deep penetration of the universe at the cost of a narrow field of view. 

“You could think of Roman as the wide-angle lens and Webb as the zoom,” McEnery explains.

Neither of these approaches to observations are better than the other—each mode just serves different purposes.  For example, Stierwalt says that if an astronomer is looking at a galaxy with Webb and notices that “it has some weird shape,” the galaxy becomes an intriguing puzzle to solve. An instrument like Webb can’t reveal the story behind that space oddity and what explains its strange shape. For that kind of cosmic detective work, Stierwalt says you need an observatory like Roman.

That balance of strengths between Webb and Roman should allow the pair to successfully collaborate. 

In addition to these differences, the duo also share some similarities. Both observatories are located nearly 1 million miles away from Earth, on the side opposite the sun, where they naturally stay quite cold. That positioning is important, since both telescopes study predominantly infrared radiation, which heat interferes with. However, Webb covers a much broader range of this light and requires the extra protection of its trademark sunshield.

Roman vs. Hubble

In many ways, Roman is more closely related to the more senior Hubble than it is to Webb. Roman and Hubble each sport the basic lipstick-tube frame that’s common among space telescopes. A round mirror of the same size, 7.9 feet across, is at each observatory’s core, although Roman’s is one-quarter the weight of its predecessor’s, contributing to the spacecraft’s agility.

Unlike Webb, both Roman and Hubble are designed for in-space maintenance. In the 1990s and 2000s, Hubble was visited by five crews of astronauts for upgrades and other work, whereas Roman’s distant outpost means that NASA would need to develop robotic servicing operations that don’t currently exist in order to refuel it. So it won’t be nearly as easy to fix as Hubble.

For this pair, the real difference comes in sensors: Roman has significantly more of them and each is much larger than their Hubble equivalent. That means that at each glance, Roman will observe a patch of the sky that is a jaw-dropping 100 times larger than that of Hubble. That means that within Roman’s initial five-year initial, it will observe 50 times the amount of sky that Hubble did during 30 full years of work.

This infographic shows the complementary capabilities of select instruments on three of NASA’s flagship missions: the Hubble Space Telescope and the currently under development Nancy Grace Roman Space Telescope and James Webb Space Telescope. Hubble views the cosmos in infrared, visible and ultraviolet light, providing a more comprehensive, high-resolution view of individual objects. The Roman Space Telescope will expand on Hubble’s infrared observations specifically, using a much larger field of view to create enormous panoramas of the universe with the same high resolution. Webb will also conduct high-resolution infrared observations, peering across farther stretches of space with a narrower field of view. Image: NASA’s Goddard Space Flight Center.

But that doesn’t make Hubble obsolete. NASA is dedicated to keeping the now 36-year-old observatory operational for as long as possible. One particular strength of Hubble compared with its successors is that it can observe in visible light and—even more importantly—ultraviolet radiation, which Earth’s atmosphere completely blocks from reaching ground-based observatories.

So although Roman represents major improvements, the beloved Hubble space telescope will always have plenty of work to do, even once its new colleague is fully operational early next year. 

“Hubble is continuing to do all of the science that it always has done because we’re not going to be using Roman in a way that could duplicate Hubble science,” McEnery says. “Hubble is going to continue to do what Hubble has always done because Roman is going to be operating in a way that Hubble can’t.”

Roman is scheduled to launch from NASA’s Kennedy Space Center in Florida on Sunday, August 30 at 7:26 a.m. EDT. 

The post How NASA’s new Nancy Grace Roman space telescope compares with Hubble and Webb appeared first on Popular Science.

A stone outcrop near the edge of the Danube River is unassuming at first glance. Most people would have a hard time picking it out from the countless other examples peaking above this portion of the river running through Budapest, Hungary. But the stone is so historically infamous that locals know it as Ínség-szikla—the Rock of Starvation. Although rarely seen, its reemergence earlier this summer is a signal of how bad the region’s ongoing drought has gotten, as well as a warning for the difficult months ahead.

Ínség-szikla is just one example of Central Europe’s many hunger stones. These geologic formations are situated in lakes or rivers, but only become visible if water levels drop too low. Budapest’s Rock of Starvation only appears when the Danube shrinks to a depth of about 37.5 inches. Once a rare occurrence, the ominous signal is becoming a more regular event thanks to the worsening climate crisis. The Rock of Starvation has reappeared in at least seven of the past 23 years, while it has shown itself at least three times this year alone.

The drought marker isn’t the result of a sudden shift in weather conditions, but one that takes months to arrive. Researchers at the International Institute for Applied Systems Analysis (IIASA) in Austria recently analyzed the Danube’s current health while also comparing it to over 30 years of data. The results showcase the effects of an unprecedented drought and multiple brutal heat waves on the river.

The current emergency began taking shape in the spring. Between April and July, rainfall throughout most of the Danube basin was far less than the 1990–2025 average. Dry years aren’t necessarily unexpected, but the 2026 drought started much earlier than usual. Beginning in June, extreme heat pushed more days above 86 degrees Fahrenheit than expected. The combination started drying out soil moisture, which put even more pressure on agricultural farmlands and native plants. In many places throughout Central Europe, July’s soil was the driest it’s ever been since at least 1990. Taken altogether, it was only a matter of time before the Danube began to reflect the conditions on land.

Over 80 million people live in the Danube basin, but the river’s low water levels will reverberate even further. Agricultural yields will almost certainly suffer, while energy infrastructure strains under the added stress. Transport routes along the Danube are also disrupted, which will slow commerce and trade.

The stone isn’t the only object to resurface as the Danube’s waters recede. Recent months have also yielded Nazi vehicles, British WWII mines, and multiple historic shipwrecks.

Budapest first began referencing the Rock of Starvation centuries ago, during an era when it originally symbolized much more localized environmental issues. But despite living in a far more interconnected world that better mitigates these emergencies, the stone still serves as a poignant—if troubling—sign of our most pressing problems.

The post ‘Rock of Starvation’ reappears in Budapest during historic drought appeared first on Popular Science.

Earlier this year, a visitor called 3I/Atlas grabbed the attention of astronomers around the world,as only the third-known interstellar object to visit our solar system. But there’s no reason for it to hog all of the limelight. A more local, icy space rock known as 220P/McNaught is currently streaking across the sky, and observers are taking note of its recent luminous transformation.

“[It] almost looks like a different comet,” astrophotographer Dan Bartlett explained on his AstroBin page.

220P/McNaught was discovered on May 20, 2004, by astronomer Robert McNaught while gazing through eastern Australia’s Siding Spring Observatory. An analysis revealed the periodic comet travels along a 5.5-year-long orbit predominantly controlled by Jupiter’s gravitational pull. This year, 220P/McNaught reached perihelion (its closest distance to the sun) on June 14 while just beyond the orbit of Mars. Since it is now traveling ahead of Earth, it’s most easily visible during dawn hours.

While generally a dimmer comet, recent activity has dramatically amplified 220P/McNaught’s brightness. In June, astronomers noted a surface eruption increased the comet’s luminosity by almost 10 magnitudes—making it around 8,000 times brighter than usual. This alone makes it one of the brightest comets ever observed, but 220P/McNaught flared by seven magnitudes yet again earlier in August. According to Universe Today, there’s a solid chance that the comet will grow more luminous at least one more time before it reaches its closest pass by Earth in October.

220P/McNaught will close out August positioned between the stars Lambda Ceti and Omicron Tauri, placing it high in the southern sky for the Northern Hemisphere through October. It will finally reach its farthest distance from the sun (its aphelion) on March 19, 2029, so its next perihelion appearance won’t occur until late 2031. However, given its luminous activity, it’s certainly possible that the comet is experiencing its death throes. If that’s the case, eagle-eyed observers may be able to witness the space rock disintegrate in real-time.

The post Look up! Now’s your chance to spot an unusually luminous comet appeared first on Popular Science.

Imagine answering the call of nature in a dark, stinking chamber alongside dozens of strangers, all while making pleasant conversation. When it’s time to wipe, perhaps you reach for a communal sponge on a stick, hoping that the person before you rinsed it well. You’re also hoping that the hole you’re sitting over won’t suddenly release rats, or flames. 

This might sound like some kind of punishment or endurance challenge today, but in Ancient Rome this was just a standard public restroom.

So what exactly was it like to use a Roman toilet? Here are all the smelly details. 

The different kinds of Roman toilet

At home, the poorest Romans relieved themselves in chamber pots. Some apartment buildings were equipped with a shared pit toilet on the ground floor, while wealthier homes might have their own private ones. Unfortunately, these private toilets were often placed near the kitchen, likely because it was also on the lowest level of a Roman home and close to a source of water for washing. 

While some of these latrines connected to pipes that moved waste underground, very few drained into Ancient Rome’s sewer system. Rome had one of the world’s first urban sewer systems, a network that included the Cloaca Maxima. Rivaling modern sewers in size and complexity, this remarkable network of tunnels dates as far back as 500 BC, and parts are still in use today, draining runoff from the Forum in the heart of the city.

Rome had one of the world’s first urban sewer systems, known as the Cloaca Maxima. Video: Ancient Rome: Cloaca Maxima, Ancient Engineering Marvel (Episode 020) | Roman History, History in Minutes: The Ancient World

But the Cloaca Maxima was primarily designed to drain marshland and alleviate flooding. Only a small portion of it was used to carry wastewater away from the empire’s capital. This meant that latrines had to be periodically emptied. 

Household slaves emptied the private toilets of the wealthy, while paid waste removers cleaned out public pit toilets and chamber pots. These paid removers would shovel waste into horse-drawn carts, which they drove out of the city at times when no other street traffic was permitted for maximum efficiency. The collected waste was then sold as fertilizer. 

The poorest Romans, often isolated on the upper floors of tenement buildings, would also empty chamber pots out of windows, although this was made illegal by the third century.

Classicist and Roman plumbing expert Ann Olga Koloski-Ostrow suggests that private toilets might have been cut off from the municipal sewers to prevent animals crawling up the pipes and into homes. And not just rats. Koloski-Ostrow cites one ancient account of an intrepid octopus, which climbed out of a toilet to devour fish stored in the household pantry.

Inside Roman public toilets

As Rome’s population grew, public toilets were installed in high-traffic areas for the free access of all (although in practice, they were used mostly by men). By the third century, the city had 144 such facilities. Known as foricae (singular forica), they are also found in other Roman settlements, such as Ostia and Pompeii.

Foricae were generally connected to city sewers and equipped with running water. Many had a channel for rinsing that ran along the floor, as well as a pool in the center of the room to help diffuse odors (how much, no one can say), and sometimes an additional washbasin. Sewage would be flushed by releasing collected rainwater or runoff from bathhouses. Foricae were typically placed near bathhouses for this reason. 

From there, the sewers carried waste off into the river or ocean, where it ran the risk of contaminating water sources. The second-century physician Galen warned against eating fish from “the outlets of rivers which clean out the sewers, the tavern, and the baths,” suggesting that at least some Romans were aware of the health risks.

What was it like to use a Roman public toilet?

Inside a forica, stone benches lined the walls, with open holes to sit on over the drainage channel below. Foricae varied widely in size. One from the Roman port of Ostia could seat 20, but the elaborate Baths of Caracalla had two adjacent restrooms seating 100 each. The absence of privacy in these open rooms was a nonissue for the Romans, who also slept, ate, and bathed in view of one another.

Public Roman bathrooms in Ostia Antica near Rome in Lazio, Italy, could seat up to 20 people at a time. Image: Sir Francis Canker Photography / Getty Images / Picasa

Lacking modern long-distance communication, Romans relished any opportunity for connecting with each other in person, even in the restroom. Ancient writers like the first-century satirist Martial described foricae as a hub for socialization. 

In one poem, Martial mocks a friend who “spends hours in all the privies, sitting all day long” in hopes of getting invited to a party: “He doesn’t want a shit. He wants a dinner.” In another poem, Martial suggests that a writer seeking fame should copy his works on the toilet walls for all to read. Even in Ancient Rome, there was toilet graffiti.

Foricae could also be quite scary. Hydrogen sulfide and methane gas rising from the cesspits were known to suddenly burst into flames, not unlike the natural phenomenon of burning marsh gas. Superstitious Romans imagined demons lurking in the darkness under the toilet seats. Many toilet walls bore images of Fortuna, the goddess of luck, just in case.

What did Romans use as “toilet paper?”

When it came to wiping, Romans had several options. The humblest was leaves or moss. One could also scrape oneself clean with discs of pottery called pessoi, made by rounding off the edges on broken potshards.

A gentler method was a natural sea sponge on a stick, known as a tersorium, which means “wiper” in Latin, or xylospongium, “sponge stick” in Ancient Greek. These were likely found in public foricae. After using a sponge stick, you would rinse it off in the running water channel if there was one, or else in a provided bucket of water or vinegar, and pass it to the next person.

As horrifying as this might sound, remember that the Romans didn’t know about germs. If something looked clean, they likely assumed it was. The sponge stick was such a normal, everyday object that it could even be used in metaphor. In a letter from the second century, a soldier named Claudius Terentianus complained about someone who “pays no more attention to me than to a sponge stick.”

What about urinals?

Standing urinals in the form of gutters are found at some Roman public buildings, such as the Colosseum. Like foricae, they were connected to running water and could be used by many people at once. 

Just as solid waste was valued as fertilizer, urine was a commodity in Roman industry due to its ammonia content. It was used for tanning leather, making toothpaste (yes, really), and most of all for cleansing and fortifying fabric in a process called fulling.

Instead of letting it all go to waste down the Cloaca Maxima, fullers and others who needed urine for their business placed pots on the streets to be filled by passersby. This resource was so valuable that the first-century Emperor Vespasian even imposed a tax on it. When his son expressed disgust at this, the Emperor is said to have replied “Pecunia non olet:” Money doesn’t stink.

Faced with the challenge of keeping their great city clean, the Romans had some solutions that were ingenious and sophisticated for their time. Still, if you ever plan on visiting Ancient Rome in a time machine, you should probably use the bathroom before you leave.

In That Time When, Popular Science tells the weirdest, surprising, and little-known stories that shaped science, engineering, and innovation.

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As the sun rose over Southern California’s Big Bear Valley on Monday morning, Shadow the bald eagle and his new companion Kaydee were spotted perched on the top of a roost tree near Shadow’s nest. 

Kaydee then visited the nest, with a feather in one of her nostrils. However, the accessory did not appear to bother her, as she got to work rearranging sticks like she and Shadow did over the weekend. Eagles frequently move around sticks to maintain their nests. Afterwards, Kaydee joined Shadow perched on another tree limb, before he flew off.

It is still too early to tell if she will be a new mate for Shadow, following the death of his former partner, Jackie, earlier this month. 

“While we will forever have our queen Jackie in our hearts, it is captivating to observe Shadow and Kaydee interacting with one another,” Friends of Big Bear Valley (FOBBV) wrote in their latest update.

FOBBV added that former executive director Sandy Steers’ message that we are mere observers of nature resonates even more right now. Steers passed away in February, following a bout with cancer.

“We will always be grateful to her for showing us the way to watch, to listen and to learn,” FOBBV writes.

Viewers can follow Shadow and Kaydee and their journey via the nest livestream.

Who is KD1 aka Kaydee?

Kaydee, formerly known as KD1, is a banded female bald eagle that has been spotted in Big Bear Valley following the death of Shadow’s former partner, Jackie. She was born in 2022, about 70 miles away from Big Bear Lake in the Prado Basin between Anaheim and Riverside, California. Coincidentally, her parents are also named Lucky and Ricky like Jackie’s parents, but they are a different eagle pair. 

Kaydee was banded as part of the Orange County Water District’s work to track the eagles born in the area. These bands help biologists track and monitor the birds over time. Kaydee currently has a black spot on her head, but it may not be permanent. It’s possible that not all of her white feathers have come in or it could be tree sap or dirt. She also has two small bands on her legs. One is a small metal band, while the other is a lavender band with “KD1” on it. 

Kaydee is almost five years old, so she is just about ready to mate. She was recently spotted on FOBBV’s livestream inspecting the nest and has also been seen hanging out near Shadow. Flying around Big Bear is completely normal behavior for young adult eagles at this time of year.

It is still too early to know if Shadow and Kaydee will mate. The full bald eagle nesting season lasts over six months, depending on when the fledged chicks leave the area. FOBBV tracks the nesting season beginning on September 1, and eggs are generally laid in January. 

Jackie and Shadow’s story

Jackie and Shadow became official in 2018. FOBBV’s nest cameras documented Jackie and Shadow’s life together, offering us a direct look into the brutality and beauty of nature. They successfully raised chicks in 2019 (Cookie and Simba) and 2022 (Spirit). The pair’s eggs failed to hatch in 2023 and 2024. In 2025, Jackie laid three eggs that all hatched in early March. However, a strong snowstorm dumped up to two feet of snow and battered the nest with strong wind and only two of the chicks (Sunny and Gizmo) survived.  

In January, Jackie laid two eggs in the nest, but ravens destroyed them. She later laid two more eggs that hatched in April and named Luna and Sandy. The name Sandy is in honor of FOBBV’s former executive director Sandy Steers who died from cancer in February. 

On July 17, Jackie was found injured on the ground near Dana Point Park, California. Cell phone video from a witness confirmed that she had an altercation with two other subadult eagles. She successfully fended off the other eagles by turning over and using her talons, but could not fly far away. 

She was transferred to the Ojai Raptor Center for care, where she was diagnosed with severe anemia. Her anemia worsened during the first week of August, the Ojai Raptor Center said that she was in unstable condition on August 9. Her packed cell volume (PCV) fell below percent, before rising to nine percent. 

Jackie died early in the morning on August 10. The necropsy did not reveal a single cause of death, and instead pointed to several factors including severe anemia, blood clots in her wing and one kidney, and liver and lung abnormalities.

The post Kaydee the bald eagle visits Shadow’s nest with a feather in her nostril appeared first on Popular Science.

The excavation of an over 400-year-old grave in Poland revealed a burial scene that, although macabre, was likely orchestrated in the hopes of protecting local villagers. In the town of Pień about 60 miles east of Kraków, archaeologists discovered the 17th century remains of a young woman interred with booby-traps to prevent her from returning as a vampire.

Researchers from Poland’s Nicolaus Copernicus University described their findings in a study recently published in the Journal of Archaeological Science: Reports. First discovered in 2022, Grave 75 contained the body of a 17 to19 year old woman who likely died sometime between 1620 and 1674 CE. DNA analysis indicates she possessed a rare maternal lineage that traces back to Scandinavia, yet remains almost nonexistent in more modern Slavic regions. Despite this genetic anomaly, examinations of her childhood teeth showed she was raised near Pień.

Archaeologists were immediately surprised by the scene inside her grave. Disrupted soil inside the burial plot suggests someone briefly dug up the body before it even finished decomposing. They then rearranged her arm towards the northeast, placed an iron sickle across her neck with the blade angled to her throat, and attached an iron padlock to her left big toe.

Both the sickle and the lock are traceable to historic folk rituals intended to combat supernatural or demonic forces. Archaeologists note that Polish-Lithuanian communities in the 17th century often blamed disease, famines, and other disasters on the recently dead—meaning this woman may have become a scapegoat for recent calamities.

However, she likely wasn’t an ostracized peasant. Thin metallic threads composed of gilded gold and silver wires that were once part of a silk cap were found near her skull. The inclusion of such a lavish accessory indicates that the young woman came from a wealthy family, although fears about potential malevolent powers didn’t stop people from taking post-burial precautions. Her status also appears to contradict hints about her health, since her nitrogen and carbon levels point to periods of malnutrition.

Meanwhile, a green stain on her neck and palate bones is likely tied to a copper-containing object or medical treatment intentionally placed deep in her mouth or nasal cavity near the time of death. Even the grave’s location suggests that a wealthy life couldn’t always guard someone against supernatural suspicions. The Pień cemetery where she is buried doesn’t appear on historical maps, and its location outside the village near a crossroads implies it functioned as a false cemetery—a site reserved for a community’s shunned individuals.

While grim, this scene illustrates the complex intersections between faith, superstition, community, and wealth within rural European life during the 17th century. But if it’s any consolation, the falsely accused vampire at least got to keep her head.

The post 400-year-old ‘vampire’ grave discovered in Poland appeared first on Popular Science.

In the United States, the Burmese python (Python bivittatus) is most often associated with zoos or the invasive chaos it’s brought to Florida over the last 50 years. That doesn’t mean the giant snake can’t potentially threaten local ecosystems in other parts of the country, too. At least 10 states including New York currently ban or heavily restrict the importation, trade, and selling of pythons.

It’s still unclear if the owner of a Burmese python understood the local laws before recently showing off his massive pet to onlookers at Coney Island in Brooklyn, New York. But according to New York State’s Department of Environmental Conservation (NYSDEC), officers were quick to inform him of the issue before confiscating the reptile.

“On July 12, [Officer] Maynard observed a large snake near Riegelmann Boardwalk in Coney Island with a crowd of about a dozen people, including small children, gathered around it,” the NYSDEC recounted in its monthly rundown of notable events.

The man, who also had a ball python (Python regius) draped around his neck, quickly admitted to owning the sizable Burmese specimen. The officer then issued a ticket for illegal possession, which likely includes a potential fine of up to $500, before confiscating the snake.

The officer couldn’t do it alone, however. Given its huge size, transporting the reptile to the Nassau County Society for the Prevention of Cruelty to Animals (SPCA) on Long Island required backup from at least one additional officer. While NYSDEC didn’t specify the snake’s exact weight and length, the announcement’s accompanying photo suggests the snake was at least 10 feet long. Burmese pythons regularly grow upwards of 16 feet long in the wild while weighing close to 200 pounds.

Unlike Florida’s hotter and more humid climate, New York State isn’t well suited for pythons outside captivity. So while it’s unlikely that local conservationists will ever need to organize their own annual python hunting challenge, the predators could still prove dangerous to native wildlife and local pets.

The post Police seize massive Burmese python near Coney Island boardwalk appeared first on Popular Science.

Signs of the waning summer are everywhere. The sun is setting earlier, yellow school buses are emerging from hibernation, and birds are showing up on weather radar once again. The fall migration is in full swing and we humans can follow along with BirdCast. 

Over the next two nights (August 25 and 26), BirdCast predicts that over 200 million birds will begin their long journey towards their head for their wintering grounds. Over 300North American bird species are long-distance migrants, meaning they will travel hundreds to thousands of miles annually. These migrations can take days to weeks, depending on the species

BirdCast’s daily forecast maps show their predicted nighttime migration patterns that begin roughly three hours after sunset. The brighter and warmer colors represent more birds expected overhead. They are also updated every six hours.

On August 25, expect the largest concentration of birds around Minnesota, North Dakota, and South Dakota. 

The data is updated every six hours, so estimates may change. Image: Van Doren, B. M., and K. G. Horton. 2018. A continental system for forecasting bird migration. Science 361:1115-1118. doi: 10.1126/science.aat7526.

On Wednesday, August 26, Iowa, Missouri, Kansas, Oklahoma, and Texas should see the highest concentration of birds.

The data is updated every six hours, so estimates may change. Image: Van Doren, B. M., and K. G. Horton. 2018. A continental system for forecasting bird migration. Science 361:1115-1118. doi: 10.1126/science.aat7526.

If you are curious which bird species may be traveling through your area, the dashboard is integrated with Cornell’s eBird database. This database uses common bird sightings from the same time in previous years to make predictions.

To make these maps, BirdCast uses weather data from the National Oceanic and Atmospheric Administration (NOAA), since their radar picks up large groups. It also uses weather forecasts to predict these nightly migration hotspots. A live map will also go up every night, so users can zero in on what might be going on in the skies where they live. BirdCast is made possible by participating scientists from Cornell University, the University of Massachusetts Amherst, Purdue University, and the University of Illinois Urbana-Champaign, and other contributors.

To migrate, or not to migrate

Typically, birds migrate for two reasons: nests and food. In the Northern Hemisphere, this means heading north during warmer months, when there are more insects and budding plant life to eat. During the spring, many species are also rushing to mate and nest. 

Ahead of the colder months, some will return south to avoid freezing temperatures. Earlier in August, a famous, toeless piping plover (Charadrius melodus) named Phoenix was spotted back in Florida, after spending the summer over 1,000 miles away in Maine. 

After spending several months in Maine, Phoenix the Footless was spotted back in Florida on August 10. Image: Lorraine Margeson.

However, not all birds head south. Many birds, including mallard ducks (Anas platyrhynchos), black-capped chickadees (Poecile atricapillus), and the turkey vulture (Cathartes aura) don’t migrate and fare just fine in snowy conditions. 

At least 4,000 bird species (or roughly 40 percent of world’s known birds) are regular migrants. The Arctic tern wins the award for longest migration of any bird in the world. These can fly almost 50,000 miles in one year, when traveling between their wintering ground in the Antarctic north to their breeding grounds in the Arctic. 

How to help migrating birds

As the migration continues over the next several weeks, there are some easy ways to help make sure that the birds safely make it to their destinations. 

• Add a film or decals to windows. This can help keep birds from colliding with the glass. 
• Plant native plants and avoid pesticides when possible. This gives them safe places to land and eat. 
• Keep cats indoors. This is good advice in general, as housecats can be destructive to the ecosystem, but rings particularly true during bird migration.  
• Turn off all excess outdoor lights. Too many lights can impact their navigation

The post Over 200 million migratory birds are hitting the sky this week appeared first on Popular Science.

Managing air traffic on a global scale requires juggling a dizzying combination of logistics, international regulations, and environmental variables. But in the not-too-distant future, commercial plane travel could feel quaint when compared to the organizational efforts needed to run humanity’s first lunar spaceport.

If all goes as planned, NASA hopes to have the Gateway installation up and running on the moon within the next 20 years. Once operational, the revolutionary orbital transportation nexus will ferry astronauts, cargo, and scientific equipment all headed to the moon’s first permanent lunar base. Setting aside everything involved in building such a vast structure, Gateway will only function safely so long as it runs on precise mathematical and gravitational calculations that simply isn’t necessary for air travel on Earth.

As researchers explain in a study recently published in the journal Acta Astronautica, these systems will all relate back to a route called the Near Rectilinear Halo Orbit (NRHO). The largely stable orbital path offers the most fuel efficient cosmic highway and an interrupted line of sight between spacecraft and mission specialists back home.

That won’t make harnessing the NRHO simple by any stretch, however. The NRHO will need to follow a highly elongated, egg-shaped loop that passes within 1,000 miles of the moon’s north pole. It will then round its turn about 40,000 miles past the lunar south pole. Thanks to physics, Gateway as well as any crew or cargo will also constantly contend with the gravitational struggle between Earth and the moon.

An artist’s concept art depicting an Orion spacecraft approaching Gateway. Credit: NASA

Then there is lunar “rush hour” to consider. Planning a single spacecraft’s trip to the moon is (relatively) straightforward, but what about when multiple crews are simultaneously en route to the moon? Just like commuting to work or taxiing on an airport runway, planning the solution comes down to loitering.

“Loitering in space means maintaining a spacecraft relative to a specific orbit or trajectory without executing an immediate maneuver,” Diane Davis, a study co-author and Texas A&M University space engineer, said in a statement.

On Earth, vehicles at rest remain at rest—at least relatively speaking. Loitering in space will involve combating orbital physics for days or even weeks at a time.

“Every spacecraft is constantly moving,” Davis explained. “It’s a Goldilocks zone of keeping ‘parked’ vehicles far enough from each other to be safe, but close enough to their destination so that resources are used efficiently.”

Davis and her colleagues from NASA and Purdue University ran thousands of computer simulations to identify the best ways to keep multiple spacecraft loitering safely near Gateway, while also including inevitable variables like thruster issues and navigational errors. They concluded that a handful of new maneuvers are necessary to ensure vehicles remain as close to their intended spots as possible. These can then be stacked as the spacecraft queue lengthens around Gateway. Davis likens the calculations to arranging a string of pearls on a necklace.

“Spacecraft would arrange themselves naturally along the lunar orbit and relative to Gateway,” she said.

Although it sounds straightforward on paper, the concepts remain incredibly complex to translate into multibillion dollar missions with dozens of lives on the line. It might not sound as dramatic as actually launching from Gateway for a lunar rendezvous, but it’s just as vital to the future of human space travel.

“The future of lunar exploration depends as much on the traffic management as it does on the rocket science,” said Davis.

The post How NASA is prepping for lunar traffic jams appeared first on Popular Science.

Earlier this year, a team of researchers in Virginia spent more than eight weeks tracking down Eastern box turtle (Terrapene carolina carolina) nests, employing a technique that seems straight out of ancient Greece’s Minotaur myth. 

The Turtle Conservation Ecology Lab has been collecting data on Eastern box turtle habits since 2022. The team started studying their nest survival rates in the spring, hoping that their research will better inform conservation leaders on how to safeguard Virginia’s native turtles’ nesting sites.

Mark Ketner, a researcher with the lab, and his field collaborator found 16 nests, but the search for each one began before the nest had even existed—with the mothers. Working with turtles that had previously been tagged with a telemetry transmitter and a GPS tag, the duo uses a VHF receiver to track down the turtle. Just like in the movies, the receiver beeps faster the closer they get to the turtle. Once the signal peaks, the researchers start looking through the underbrush. 

If they find a turtle, the duo note down basic information about the reptile before checking to see if the (presumably female) turtle is carrying eggs, which would make her a gravid turtle. To check for eggs, the scientists feel for a hard bulge under the skin just above the hind legs. This approach, however, doesn’t always provide a definitive answer, and is where the portable X-ray machine comes in. 

This photo is from fieldwork of a research project investigating survival rates for wild box turtle nests. Photos were taken in May 2026 at an undisclosed field site in rural Virginia. The team tracks box turtles using a GPS locator, a telemetry unit, with trackers gently fixed to the backs of the turtles’ shells. Julia Jones operates a portable X-ray machine to confirm if the turtles are carrying eggs. Image: Smithsonian/Joe Kolowski. Joe Kolowski

To make sure the turtle doesn’t move around, they place the reptile on top of an upside down cup as a veterinary technician captures an X-ray scan. If the scan reveals that the turtle is carrying eggs, the two researchers record it and then attach a spool to the turtle’s shell. They then return her to where she’d been discovered and tie the end of the thread to a small flag. 

The researchers are essentially the Ariadne to the turtle’s Theseus. The mothers-to-be pull the thread along like the Greek hero did as he wandered through the minotaur’s labyrinth. The researchers then return the next day, track down the turtles, and weigh them. If the turtle weighs less than before, it means that she’d laid her eggs in the vicinity. 

“At this point we’re usually bent over, following this thin piece of thread for hundreds of feet… we look kind of silly doing it,” Ketner said in the statement. 

Once a nest is discovered, Ketner and his field collaborator plant a small flag, take down some associated information, and set up a camera to keep an eye on it remotely. 

Eastern box turtle (Terrapene carolina carolina). NZCBI’s Turtle Conservation Ecology Lab is monitoring populations across landscapes with the goal to develop best management practices that private landowners can implement to support turtle conservation. Image: Smithsonian/Brooke McDonough. Brooke McDonough

Eastern box turtle eggs hatch after around two months,but not all of the 16 nests that the team identified made it. In fact, the eggs from 13 of those nests were quickly destroyed and eaten by predators. Box turtle nest predation may be up to 90 percent, according to the team.

“Nest predation adds a layer to turtle population decline that I don’t think many people are aware of,” Ketner explained. “It’s easy to picture a turtle’s biggest threat as a spray of pesticide or a car on a country road. But we’re seeing they’re in danger before they’ve even hatched.”

This racoon was caught eating a nest on our trail camera. You can see the turtle egg in its mouth. This image is from fieldwork of a research project investigating survival rates for wild box turtle nests. Photos were taken in May 2026 at an undisclosed field site in rural Virginia. Image: Smithsonian/Mark Ketner.
Mark Ketner

The data the team collected this season doesn’t change anything for these hatchlings, but it does shed light on the factors currently threatening this species, and the more scientists know about an animal, the better equipped they are to protect it. There’s still a lot to learn, however, and next year the Turtle Conservation Ecology Lab will be gathering further nest information. 

“Collecting all the right the data is a slow, steady process,” said Ketner, “but they’re turtles. They figured this out over 200 million years ago, and they know exactly what they need. Our goal is to figure that out too, but in less time.”

The post How do you find Eastern box turtle nests? You’ll need a spool of thread. appeared first on Popular Science.

Many cosmic images don’t quite look like the nicknames astronomers bestow upon them. Case in point: the Crab Nebula. The Hubble Space Telescope’s portrait of the star factory looks more like an amorphous blob than a crustacean, and it’s still hard to envision a clawed creature in 19th century astronomer William Parsons’ early sketch of the nebula.

This isn’t always the case, though. The James Webb Space Telescope’s (JWST) recent glimpse at a region inside the Carina Nebula lives up to its nickname. Looking at the image taken using JWST’s Near-Infrared Camera (NIRCam), it’s difficult to see anything other than a cosmic Treasure Chest.

The Treasure Chest’s unique shape is likely influenced by a massive nearby binary star. Credit: ESA/Webb, NASA & CSA, M. Reiter
Acknowledgement: M. H. Özsaraç ESA/Webb, NASA & CSA, M. ReiterAcknowledgement: M. H. Özsaraç

Located about 7,500 light-years from Earth, the Treasure Chest is filled with metaphorical jewels instead of literal gold. The formation is a cometary globule—a distant cloud with a dense head and flowing tail composed of dust and gas that looks a bit like a comet. Many cometary globules may look a bit like their comet namesakes, but the Treasure Chest feels more appropriate in this case…that, or a large recliner chair.

Astronomers estimate around 70 young stars and nascent protostars reside in Carina’s cometary globule, one of which is an example of a rare O-type star that’s about 19 times more massive than the sun. Even at an estimated 1.3 million years old, the Treasure Chest houses stars so young that they are still encased in their gassy, dusty circumstellar discs(also known as protoplanetary discs).

The culprit responsible for the Treasure Chest’s unique shape is located 39 light-years away, outside the image’s field of vision. The stellar system Eta Carinae is the brightest object in the Carina Nebula. It technically includes two or more stars, and one of its stars is estimated to be 100 times more massive and five million times as luminous than the sun. Together with a nearby star cluster called Trumpler 16, the overall stellar radiation and winds from Eta Carinae and Trumpler 16 are likely influencing the Treasure Chest’s shape.

Astronomers theorize that the star cluster initially coalesced in a larger gas cloud before neighboring stars eradicated the less-dense materials. This left only the denser cometary globule and its recognizable structure. Beyond serving as an interstellar Rorschach test, analyzing subjects like the Treasure Chest helps researchers better understand how young stars amass and eject gas, and how these behaviors influence their local cosmic neighborhoods.

The post ‘Treasure Chest’ cosmic cloud glitters with dozens of young stars appeared first on Popular Science.