Instead of putting the pedal to the metal, a team of scientists from Japan and Taiwan are putting the paddle to the water–for science. The team used time-period-accurate tools to create canoes and used them to test the methods that ancient people would have used to travel across the sea in East Asia 30,000 years ago. Their results of these test paddles and findings are detailed in two new studies published June 25 in the journal Science Advances. 

Archaeological evidence suggests that about 30,000 years ago, humans first made a crossing from present-day Taiwan to islands in southern Japan. This journey could have ranged from 138 to about 450 miles and was accomplished without metal tools, maps, or modern boats. While the timeline of when East Asia’s earliest modern human populations set sail and where they landed is fairly clear, how they did it has been more difficult to pin down. That’s where these replica canoes come in. 

A team led by anthropologist Yousuke Kaifu from the University of Tokyo created various simulations, experiments, and replica canoes to recreate how this feat may have been achieved. 

“We initiated this project with simple questions: ‘How did Paleolithic people arrive at such remote islands as Okinawa?’ ‘How difficult was their journey?’ ‘And what tools and strategies did they use?’” Kaifu said in a statement. “Archaeological evidence such as remains and artifacts can’t paint a full picture as the nature of the sea is that it washes such things away. So, we turned to the idea of experimental archaeology, in a similar vein to the Kon-Tiki expedition of 1947 by Norwegian explorer Thor Heyerdahl.”

One of the new studies details the construction and testing of a real boat, which the team successfully used to paddle between islands. The team constructed the 24-foot-long dugout canoe called Sugime in 2019. It was built from one Japanese cedar trunk, and with replicas of 30,000-year-old stone tools. 

“A dugout canoe was our last candidate among the possible Paleolithic seagoing crafts for the region. We first hypothesized that Paleolithic people used rafts, but after a series of experiments, we learned that these rafts are too slow to cross the Kuroshio and are not durable enough,” said Kaifu.

The team paddled Sugiume about 140 miles from eastern Taiwan to Yonaguni Island in southern Japan’s Ryukyu group, which includes Okinawa. They navigated only by the sun, stars, swells, and their instincts. In total, the team paddled for more than 45 hours across open sea, without a lot of visibility of the island. In the six years since, the team is still unpacking some of the data they collected during the experiment, and are using it to inform or test new models about various aspects of Paleolithic sea crossings.

[ Related: Southeast Asian sailors possibly mastered seafaring before Polynesians. ]

“We now know that these canoes are fast and durable enough to make the crossing, but that’s only half the story,” said Kaifu. “Those male and female pioneers must have all been experienced paddlers with effective strategies and a strong will to explore the unknown.”

However, the team does not think that a return journey towards Taiwan was possible at the time.

“If you have a map and know the flow pattern of the Kuroshio, you can plan a return journey, but such things probably did not take place until much later in history,” explained Kaifu.

The team also used advanced ocean models to simulate hundreds of virtual voyages, in an effort to understand if a journey like the one the modern scientists tried could have been made in different circumstances. These simulations tested several variables, including different starting points, seasons, and paddling strategies under both ancient and modern ocean conditions.

Additionally, one of the new papers used numerical simulations to show how they may have crossed the Kuroshio Current–one of the strongest currents in the world. This simulation showed how boats made using tools of the time, and the right know-how, could have navigated the Kuroshio Current.

“The Kuroshio Current is generally considered dangerous to navigate,” Yu-Lin Chang, a study coauthor and oceanography student from the Japan Agency for Marine-Earth Science and Technology, said in a statement. “I thought if you entered it, you could only drift aimlessly. But the results of our simulations went far beyond what I had imagined. I’m pleased this work helped illuminate how ocean voyages may have occurred 30,000 years ago.”

These various simulations helped fill in some gaps that a simple one-time experiment could not. They also revealed that launching a vessel from northern Taiwan offered seafarers a better chance of success than from points further south. Additionally, paddling slightly southeast instead of directly towards the destination was essential for compensating against the powerful ocean current. 

All in all, these findings suggest that the early modern humans in the area must have had a high level of strategic seafaring knowledge.

“Scientists try to reconstruct the processes of past human migrations, but it is often difficult to examine how challenging they really were. One important message from the whole project was that our Paleolithic ancestors were real challengers. Like us today, they had to undertake strategic challenges to advance,” said Kaifu. “For example, the ancient Polynesian people had no maps, but they could travel almost the entire Pacific. There are a variety of signs on the ocean to know the right direction, such as visible land masses, heavenly bodies, swells and winds. We learned parts of such techniques ourselves along the way.”

The post Ancient canoe replica recreates a 30,000-year-old voyage appeared first on Popular Science.

Rhythmic pulsing deep beneath landlocked east Africa is literally tearing the continent apart. But while the effects won’t arrive on the planet’s surface for a while, the end result is an entirely new ocean basin above it. An international research team reached their conclusion after analyzing more than 130 samples from young volcanoes located across a rare geological region below Ethiopia. The evidence is laid out in a study published on June 25 in the journal Nature Geoscience.

The Afar Rift zone is one of the few examples on Earth where three tectonic rifts converge. Experts previously theorized this juncture of the Main Ethiopian, Red Sea, and Gulf of Aden Rifts contained an active, hot upwelling of molten mantle. If true, this area—often known as a plume—would display clear effects on the tectonic plates above it. Rift zones typically stretch and pull tectonic plates until they eventually rupture. But how the plume beneath Afar’s is structured, how it behaves, and how it is influencing the crust above it have remained mysteries.

To investigate, a 10-institution team led by Swansea University geoscientist Emma Watts traveled to Ethiopia where they collected over 130 rock samples from both the Afar region and the Main Ethiopian Rift. Researchers then combined sample analysis with existing data and advanced statistical modeling to explore the area’s crust and mantle dynamics. As suspected, the Afar mantle plume isn’t uniform or static.

“It pulses, and these pulses carry distinct chemical signatures,” Watts said in a statement. “These ascending pulses of partially molten mantle are channelled by the rifting plates above. That’s important for how we think about the interaction between Earth’s interior and its surface.”

Tom Gernon, a University of Southampton earth science professor and study co-author, likened the chemical striping to a heartbeat.

“These pulses appear to behave differently depending on the thickness of the plate, and how fast it’s pulling apart,” he added. “In faster-spreading rifts like the Red Sea, the pulses travel more efficiently and regularly like a pulse through a narrow artery.”

The team also confirmed that deep mantle upwellings are closely tied to tectonic plate motion. According to study co-author and earth scientist Derek Keir, the findings have “profound implications” for how geologists can better understand surface volcanism, earthquakes, and continental breakups.

As to when Earth will see the birth of a new ocean basin—experts like Watts aren’t sure. But that doesn’t mean anyone needs to start worrying.

“In terms of timescales—it’s hard to put an exact number to it given that rifting rates can change, so to be honest we can’t know for sure,” Watts told Popular Science in an email. She noted for reference that their study area’s rifting rates range between just 5-16 millimeters each year.

“[So] one thing we do know is that it will be on the order of millions of years,” she added. “Hopefully, our next work will get closer to some probabilistic estimates.” 

CORRECTION: 6/25/25 12:50PM: A previous version of this article misidentified the annual rift rate cited by Watts.

The post A new ocean is forming in East Africa appeared first on Popular Science.

While tariffs are front and center in the news, Ford isn’t worried about its Expedition SUV. Every Expedition is made at Ford’s Kentucky Truck Plant, where the automaker uses a combination of high-tech machinery, software, and a skilled labor force to build the Expedition, alongside the F-250–F-550 Super Duty trucks and the Lincoln Navigator SUV. Inside the plant, workers on the production line are operating as smoothly as a choreographed ballet. Under the vehicles in a trench, technicians install HVAC lines while above, horns and revving engines punctuate the constant hum.

It’s here that the new, fully redesigned Ford Expedition is built, boasting several improvements for 2025. The Expedition includes a new front suspension and shocks as well as enhancements to the frame and stabilizer bar, rear end, and body mounts. Plus, the new Expedition can tow 300 more pounds than its predecessor, for a total of 9,600 pounds, a benefit to those who like to travel with other people, pets, and camping gear or motorsports equipment.

Ford also unveiled the Expedition Tremor, a new off-road version of the SUV, which includes 33-inch all-terrain tires, available hands-free Blue Cruise driving, and a new split tailgate. Every Expedition comes with a twin-turbo 3.5-liter V6 and a 10-speed automatic transmission. The standard output is 400 horsepower and 480 pound-feet of torque, while a high-output version (standard on the Tremor, optional on Platinum trims) generates 440 hp and 510 lb-ft of torque. All that power propels the big SUV forward and supports its towing prowess. 

The towing experience is important, because 40-50% of Ford customers tow between two times a six times a year, says Expedition vehicle engineering manager Kartik Ramanathan. The need isn’t frequent, but consumers tend to buy SUVs and pickup trucks for the possibilities of what they can do, just in case. (If that’s you, just remember that means that friends may call on you to help them move, or rope you into towing a camper for the weekend.) 

To increase the towing capacity for the 2025 model, Ramanathan says the engineers “watch the weight of the vehicle like a hawk.” The heavier the vehicle, the less towing capacity is available for the same set of components. 

“The way towing capacity works is this: You have the gross combined weight rating of the vehicle, which is a combination of the base curb weight of the vehicle, trailer, and passengers,” Ramanathan explains. “As you increase the base curve, the combined weight rating stays constant. Now, you can change it by changing the components, but then you get into the circular loop of making the components heavier so they’re more durable and then, because you have more weight now, you have a higher base curve and you can tow less. It’s a balance.” 

Another factor is thermal management. If the cooling system overheats and isn’t working right, the vehicle won’t be able to tow as much, so there are multiple restrictions. 

“When we do a towing analysis, we actually look at multiple components at the same time and try to determine what is our weakest link, and then we make sure that we shore up that weakest link,” Ramanathan says. “In this case, to increase our max towing we had to up our cooling system capability.”

Ford opted to replace the 16mm radiator with a 26mm radiator, which allowed the Expedition engineers to achieve the higher towing number. 

For the new Expedition, the entire upper body sits on flexible rubber body mounts that attach the body to the frame and absorb up-and-down motion. As such, the mounts need to be much softer than the frame and the body so it can compress and convert that energy into heat and dissipate that energy.

“For example, when you take a stress ball and you squeeze it, then let it go, you’re taking  energy from your body and you’re squeezing it into the ball so the ball takes that energy,” Ramanathan explains. “When it compresses, you’re not able to sense a temperature change, but essentially what’s happening is it absorbs that energy and converts [it] into heat.” 

Ford changed the damping properties of the body mounts, adjusting the stiffness of the rubber and how “squishy” it is, he says, which results in improvements in how much squish is converted into heat energy. It’s also more complicated than just making the rubber mounts softer; the results depend on the frequency response to the vibration.  

Engineers used an accelerometer, a device that measures the vibration or acceleration of motion. Ford uses high-tech mannequins inside the vehicle that can measure sound coming from all directions, and accelerometers are positioned on the floor pan and the seats. Essentially, this set-up measures how much acceleration passengers will feel. Once that measurement is obtained, the team uses a mathematical process called the Fourier transform to identify any problematic frequencies that might be causing undue vibration. From those measurements, the engineers tune the damping and make improvements.

“Tuning changes the stiffness and damping coefficient in the mount so that at that location on the frame, it’s absorbing the most energy possible, and you’re getting the least amount transmitted into the body,” Ramanathan says.

All in, the 2025 Expedition is better suited for both on- and off-road use than previous iterations. The body mounts and shocks make for a smoother ride for the driver and passengers, and towing improvements mean you can bring more gear or a bigger camper in the process without feeling every bump on the road.

The post How the 2025 Ford Expedition tows more, with less vibration appeared first on Popular Science.

Many of us have been there, wide awake at 2 a.m., thanks to a snoring partner, noisy neighbors, or the relentless hum of city life. Sleep doesn’t always come easily, but the right tools can make a world of difference.

That’s where SleepEEZ can be immensely useful. They are mini, wireless earbuds designed with one goal in mind—helping you fall asleep faster and stay asleep longer. And for a limited time, they’re just $25.99 (reg. $34.99) with free shipping.

What makes SleepEEZ different? For starters, they’re tiny—just three grams each—and shaped to fit snugly without putting pressure on your ears. Whether you’re a side sleeper, back sleeper, or someone who flops around like a fish, these won’t dig in or fall out. The soft silicone and breathable ErgoLoops help keep things secure and comfy all night.

But comfort is only part of the story. These earbuds block out up to 20 decibels of ambient sound—so snoring, TV noise, or even early-morning garbage trucks get dialed way down. Pair them with your favorite relaxation app, white noise playlist, or even a meditation podcast, and you’re setting the scene for your most peaceful sleep yet.

SleepEEZ also features a custom sleep timer, so they shut off automatically—saving battery and letting your mind fully drift. Bluetooth 5.4 ensures a stable connection, even when you toss and turn, and the built-in microphones allow you to use them for calls or voice assistants as well.

Whether you’re sharing a room, living in a noisy neighborhood, or just want to make bedtime a little more tranquil, SleepEEZ is a smart, comfortable upgrade. And with this exclusive pricing, you don’t have to lose sleep over the cost.

Pick up the CES-featured SleepEEZ mini noise-blocking sleep earbuds while they’re on sale for $25.99 (reg. $34.99) with free shipping.

StackSocial prices subject to change.

_

SleepEEZ Mini Noise-Blocking True Wireless Earbuds for Sleeping

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The post Get the rest you deserve with these $26 mini sleep earbuds appeared first on Popular Science.

Power tool batteries have a lot of bad habits. They walk away when you’re not looking. They run out of charge when you have a job to do. They give you the blinking light of death when you put them on the charger. This is why you can never have too many batteries. Right now, Home Depot has its early 4th of July sale running, and it includes a ridiculous Ryobi deal. It includes a pair of batteries, a charger, and your choice of a free tool. That’s solid value, even if you’re picking up a tool you only need occasionally.

Ryobi

This kit offers a pair of batteries. The larger cell offers 4.0 Ah, while the smaller version checks in at 2.0 Ah. These aren’t the biggest batteries Ryobi offers, but they charge quickly, handle nicely, and work across the company’s entire arsenal of electric power tools. When you add the batteries to your cart, be sure to add the free tool using the prompt on the right side of the Home Depot site. Here’s a list of the tools you can choose from—the most expensive offers a $79 in extra value for free:

• ONE+ 18V Cordless Reciprocating Saw (Tool Only)
• ONE+ 18V Cordless Jig Saw (Tool Only)
• ONE+ 18V Cordless VERSE Clamp Speaker (Tool Only)
• ONE+ 18V Cordless Hybrid WHISPER SERIES 7-1/2 in. Fan (Tool Only)
• ONE+ 18V 90 MPH 250 CFM Cordless Battery Leaf Blower (Tool Only)
• ONE+ 18V Cordless Wet/Dry Hand Vacuum (Tool Only)
• ONE+ 18V Cordless Oscillating Multi-Tool (Tool Only)
• ONE+ 18V Cordless Dual Function Inflator/Deflator(Tool Only)
• ONE+ 18V Hybrid LED Work Light (Tool Only)
• ONE+ 18V 18 in. Cordless Battery Hedge Trimmer (Tool Only)
• ONE+ 18V Cordless 5 in. Random Orbit Sander (Tool Only)
• ONE+ 18V Cordless 10 oz. Caulk & Adhesive Gun (Tool Only)
• ONE+ 18V Cordless VORTEX Power Scrubber (Tool Only)

Ryobi

If you don’t mind spending more cash, you can get a trio of high-performance batteries, which drastically increases your overall runtime. This deal also comes with a higher-end free tool with a value up to $199. Here’s a complete list of the tools available:

• Hybrid Tri-Power Tripod Light (Tool Only)
• ONE+ HP 18V Brushless Whisper Series 130 MPH 450 CFM Cordless Battery Leaf Blower (Tool Only)
• ONE+ HP 18V Cordless Pet Stick Vacuum Cleaner (Tool Only)
• ONE+ 18V Cordless VERSE Clamp Speaker (Tool Only)
• ONE+ HP 18V 18-Gauge Brushless Cordless AirStrike Brad Nailer (Tool Only)
• ONE+ 18V Cordless Jig Saw (Tool Only)
• ONE+ HP 18V Brushless Cordless 4-Mode 1/2 in. Impact Wrench (Tool Only)
• ONE+ 18V Cordless Hybrid WHISPER SERIES 7-1/2 in. Fan (Tool Only)
• ONE+ 18V 90 MPH 250 CFM Cordless Battery Leaf Blower (Tool Only)
• ONE+ HP 18V Brushless Cordless 4-1/2 in. Angle Grinder (Tool Only)
• ONE+ HP 18V Brushless Cordless Compact 6-1/2 in. Circular Saw (Tool Only)
• ONE+ 18V Cordless Dual Function Inflator/Deflator(Tool Only)
• ONE+ HP 18V Brushless Cordless Compact One-Handed Reciprocating Saw (Tool Only)
• ONE+ 18V Cordless Oscillating Multi-Tool (Tool Only)
• ONE+ 18V Cordless Reciprocating Saw (Tool Only)
• ONE+ 18V Cordless VORTEX Power Scrubber (Tool Only)
• ONE+ 18V Cordless Wet/Dry Hand Vacuum (Tool Only)
• ONE+ 18V 18 in. Cordless Battery Hedge Trimmer (Tool Only)
• ONE+ 18V Hybrid LED Work Light (Tool Only)
• ONE+ 18V Cordless 5 in. Random Orbit Sander (Tool Only)
• ONE+ 18V Cordless 10 oz. Caulk & Adhesive Gun (Tool Only)

Ryobi

If you want to jump full-force into the Ryobi system, you can grab this six-tool combo kit, which comes with a pair of batteries, a charger, and a bag in which to carry everything. This is the classic kit of power tools, including:

• Impact driver
• Drill
• Reciprocating saw
• Circular saw
• Oscillating tool
• Flashlight

That’s basically everything you need to demolish and rebuild a room. Grab the $99 battery kit above and add a free tool and more battery power to your arsenal.

• ONE+ HP 18V Brushless Cordless 7-1/4 in. Circular Saw (Tool Only) $99 (was $129)
• ONE+ HP 18V Brushless Cordless 10 in. Sliding Compound Miter Saw Kit with 4.0 Ah HIGH PERFORMANCE Battery and Charger $329 (was $399)
• ONE+ HP 18V Brushless Cordless Reciprocating Saw (Tool Only) $89 (was $116)
• ONE+ HP 18V Brushless Cordless Compact 1/2 in. Drill and Impact Driver Kit with (2) 1.5 Ah Batteries, Charger, and Bag $149 (was $179)
• USB Lithium Clamp Fan Kit 2-Pack with (2) 2.0 Ah USB Lithium Batteries and Charging Cable $59 (was $79)
• ONE+ 18V Cordless 2-Tool Combo Kit with Drill/Driver, Impact Driver, (2) 1.5 Ah Batteries, and Charger $99 (was $139)

The post Get A Ryobi power tool, two batteries, and a charger for just $99 during Home Depot’s early 4th of July sale appeared first on Popular Science.

In 2020, archaeologists in Ireland first announced a startling find at Newgrange, a giant Neolithic burial chamber 30 miles north of Dublin. Genetic analysis of the 5,000-year-old human skull fragments indicated that the man was the product of an incestuous relationship, either between siblings or a parent and their own child.

Experts offered a headline-grabbing theory: Neolithic Ireland was ruled by incestuous royal dynasties, or potentially even “god-kings” similar to those documented in ancient Egyptian and Incan empires. Dating back roughly 500 years before both Stonehenge and the Giza pyramids), the UNESCO World Heritage Site contains the remains of numerous Stone Age individuals. Combined with evidence of genetic relations in other passage tombs on the island, according to another team led by researchers at the University College Dublin, the Newgrange god-king hypothesis doesn’t hold up to closer scrutiny. Their argument is laid out in a study published on June 22 in the journal Antiquity.

Constructed around 3100 BCE, Newgrange includes a massive burial mound built from an estimated 196,000 tons of layered earth and stone. The site has featured prominently in Irish culture for millennia, with folklore eventually ascribing the chambers as home to the region’s chief god Dagda and his son Aengus. Antiquarians first rediscovered Newgrange in 1699 CE, but the most thorough excavation work at the site began in 1962. Experts have continued exploring the Stone Age trove—including the controversial skull fragment known as NG10.

Dating between 3340 and 3020 BCE, NG10 potentially offered, “far-reaching consequences for our understanding of prehistoric population movement and the structure of that ancient society,” according to the 2020 study’s accompanying report in Nature.

“Socially sanctioned matings of this nature are very rare, and are documented almost exclusively among politico-religious elites—specifically within polygynous and patrilineal royal families that are headed by god-kings,” the authors noted at the time.

Archeologist Jessica Smyth disagrees. As one of the latest study’s co-authors and an associate professor at University College Dublin, Smyth has serious doubts about NG10’s royal pedigree.

“People were definitely being selected for burial in passage tombs—the whole community does not end up in these monuments,” Smyth explained in a statement. “However, we don’t know the reasons behind this selection, and why they were thought to be special.”

Smyth and her colleagues argue that many of the site’s other skeletal remains simply don’t support the idea of pervasive incest among those buried at Newgrange. Instead, they say the genetic clustering found amid bones in specific passage tombs more typically reflects distant biological relations such as second cousins and even great-great-great-grand parents.  With this knowledge, Smyth and co-authors believe the burials weren’t solely determined by lineage or royal dynasty, but potentially along more communal, egalitarian lines.

“We now have some really great examples of monuments elsewhere in Europe that contain people with very close biological ties—parents, children, grandparents, etc.,” said Smyth. “This sort of [ancient DNA] evidence is much closer to the idea of a lineage or dynasty. [But] we do not see this evidence in Irish passage tombs.”

What’s more, a deceased person’s remains were treated differently during Neolithic Ireland than they are today.

“Unlike today, bodies don’t tend to be buried ‘whole’ or ‘intact’ in this time period. Before they end up in megalithic monuments, bodies are broken down, sometimes cremated and even circulated around their communities,” added Smyth.

Until recently, archaeologists have largely examined Irish megaliths and their passage tombs individually from each other, instead of in a broader context of the communities that surrounded them. Taken altogether, the team believes it remains difficult to extrapolate dynastic dynamics from a single skull fragment.

“A one-off example of incest is a shaky foundation on which to reconstruct an elite, let alone a specific social [hierarchy],” the study authors contend, adding that doing so may incorrectly further the myth that only important males were socially relevant.

“[It] doesn’t make sense to continue to focus so exclusively on forms of stable, individual rule, in Neolithic Ireland and elsewhere, when the evidence is insufficient to support such claims,” they wrote. “It downplays the contribution made by collective action in the prehistoric past.”

The post Incestuous ‘god-kings’ may not have ruled Stone Age Ireland after all appeared first on Popular Science.

The summer heat is on for millions and no matter your animal species, keeping our bodies cool is critical for survival. Humans seek out shade, water for swimming, and some deploy the uniquely-human technique of “sitting in the air conditioning and barely moving.” Other mammals spread out on the grass or sploot to help regulate their body temperature and keep cool. 

For some turtles, it’s basking or the “Superman pose” that helps keep their bodies at the right temperature and much more. According to Everglades National Park in southern Florida, Florida redbelly turtles (Pseudemys nelsoni) are often seen with their limbs and/or necks stretched out in order to soak up as much sunlight as possible. It appears to work similarly to yoga in humans, with several benefits. It can warm up their bodies, boost their digestion, help make Vitamin D3 for stronger shells and bones, and importantly helps prevent infection. 

Basking helps the turtles dry out their shells, which can keep dangerous parasites from attaching. Ectoparasites–or harmful organisms located on the outside of an animal–like leeches can cause anemia in turtles, according to Canada’s Think Turtle Conservation Initiative. Since being out in the direct sunlight is not a great environment for the leeches, they will go away and leave the turtles alone. 

While you may have been taught that all reptiles are cold-blooded and mammals are warm-blooded, there is more nuance than that in the animal kingdom. Birds, mammals, and some fish (including some living and extinct shark species) are considered endotherms. This means that they maintain a constant body temperature that is independent of their environment. Humans also fall into this endothermic camp.

[ Related: Turtle’s mysterious injury caused by a golf ball. ]

Other fish species, amphibians, and reptiles like turtles are considered ectotherms. As an ectotherm, a turtles’ body temperature changes alongside the environment around them. To help regulate their body temperature, turtles will bask on logs, fallen trees, rocks, and other surfaces in the sunlight with their limbs stretched out. Having access to safe basking sites in lakes, ponds, or marshes is crucial for this reason. Some snapping turtles will try to bask on hot asphalt, which can increase their risk of getting run over by a car. 

Since basking is a completely normal activity for turtles, it’s important to safely observe them from a distance and leave them alone. However, if a turtle shows signs of distress, including heavy bleeding, injuries to their shell, or disorientation, call a local animal rescue or veterinarian’s office and get their instructions on what to do. 

This story is part of Popular Science’s Ask Us Anything series, where we answer your most outlandish, mind-burning questions, from the ordinary to the off-the-wall. Have something you’ve always wanted to know? Ask us.

The post Why do turtles do the ‘Superman pose’? appeared first on Popular Science.

Between gnarly storms and brutal heat, power outages have been a common occurrence this spring and summer here in Upstate New York. As a result, my assortment of portable power stations and solar generators have been getting regular use. Right now, Bluetti has just about every portable power station it makes for the lowest price of the season. These have a tendency to go out of stock or on backorder once the storm season really gets into full swing, so grab one now and have it when you need it. You don’t have to be a prepper to appreciate electricity when the grid is down.

Bluetti

This is a great size if you just want to keep[ some essential devices alive when the grid goes down, or you want to take it camping. It’s smaller than a typical cooler and weighs just 22.5 pounds. But, its 768Wh capacity is enough to power critical devices like CPAP machines and fully recharge smartphones, tablets, and laptops. I have used a solar generator this size to keep my internet connection running because the people need deals whether the grid is working or not.

It offers a pair of typical AC outlets, two USB-A ports, and two USB-C ports. The DC out makes it great for RV living or camping. Plus, this is a newer LiFePO4 battery, which lasts much longer than the older lithium ion models, even with very regular use.

Bluett

If you just want something to keep all of your devices up and running, this compact model is a great way to do it on the cheap. It weighs less than eight pounds and includes a total of eight outlets: a pair of AC outlets, three USBs, and a DC out. It charges up quickly and stores easily with your emergency or camping gear.

Bluetti

This 54-pound model offers a ton of capacity for powering larger devices. Built-in handles make it relatively easy to lug around. There are four AC outlets on the front, as well as four USB ports. Deals on this model only typically last a few days, so if you want one of these for cheaper than its $1,699 regular price, don’t sleep on it.

• BLUETTI Solar Generator AC300 & B300K Expansion Battery $1,399 (was $2,499)
• BLUETTI Solar Generator AC200L, 2048Wh LiFePO4 Battery Backup $997 (was $1,599)
• BLUETTI Solar Generator AC180, 1152Wh LiFePO4 Battery Backup $448 (was $699)
• BLUETTI Solar Generator AC500 & B300K Expansion Battery, 2764.8Wh LiFePO4 Battery Generator $1,799 (was $2,799)
• BLUETTI 100W Solar Panel for Solar Generator $168 (was $299)
• BLUETTI Solar Generator AC500 & B300K Expansion Battery $1,799 (was $2,799)
• BLUETTI Portable Power Station AC180P $499 (was $899)
• BLUETTI Solar Generator AC500 & 2 B300K Expansion Batteries with 2 200W Solar Panels Included $3,199 (was $4,599)

The post Amazon dropped Bluetti solar generators to their lowest prices of the year just in time for summer storms appeared first on Popular Science.

Do you have a dusty old PC lying around? Give it a totally new lease on life with Microsoft Windows 11 Pro. This operating system can breathe new life into old computers, and right now it’s only $14.97 (reg. $199) through June 29.

Don’t shell out hundreds of dollars for a new computer—just $15 will make an old device feel brand new. Microsoft Windows 11 Pro can give your PC a total refresh, with an updated, seamless interface, snap layouts, improved voice typing, a more powerful search experience, and your very own AI-powered assistant, Copilot, on your desktop.

Windows 11 Pro is designed for today’s professionals, so you can enjoy updates that will give you a much-needed productivity boost this summer and beyond. Get access to Microsoft Teams, Azure AD, Hyper-V, and Windows Sandbox.

Windows 11 Pro also enhances your online security, offering advanced features like biometric logins, encrypted authentication, and enhanced antivirus protection to help keep your data safe.

This operating system requires 4GB RAM and 40GB of hard drive space to run.

Act fast to outfit your PC with Microsoft Windows 11 Pro for only $14.97 (reg. $199), now through June 29.

StackSocial prices subject to change.

Microsoft Windows 11 Pro

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The post Your old PC called — it wants Windows 11 Pro for $15 appeared first on Popular Science.

On December 5, 2020, a small capsule jettisoned from Japan’s Hayabusa2 spacecraft as it made a scheduled flyby over Earth. The payload landed in the Australian outback as planned, capping a 6-year roundtrip journey to survey the asteroid Ryugu. Since then, researchers including a team at Hiroshima University, have analyzed the unprecedented mineral samples collected from the distant space rock. But according to their most recent findings, published in the journal Meteoritics & Planetary Science, one of those minerals defies planetary scientists’ previous theories on Ryugu’s creation. The consequences may help clarify the solar system’s evolution, and the surprising complexities inside some of its most primitive asteroids.

To understand Ryugu, it’s important to first understand its origins. Researchers believe the half-mile wide, 496-million-ton rock belongs to a parent body that formed 1.8–2.9 million years after the birth of our solar system. This asteroid family—likely Eulalia or Polana—coalesced from icy mixtures of carbon dioxide and water at the outer edges of the solar system. Over millions of years, radioactive elements decayed and generated heat inside the parent body to likely reach around 122 degrees Fahrenheit. It’s believed that a catastrophic impact with another asteroid created the carbon-heavy Ryugu, which is composed of rocks similar to the CI chondrite meteorites that frequently streak through Earth’s atmosphere.

But while CI chondrites are commonplace, enstatite chondrites are not. These rare asteroids form under extremely high temperature conditions inside the solar system’s inner region. Enstatite chondrites contain different minerals such as djerfisherite, a potassium-laden iron-nickel sulfide. Based on everything scientists know about asteroids, Ryugu shouldn’t include an ingredient like djerfisherite—but it does.

“Its occurrence is like finding a tropical seed in Arctic ice,” said Masaaki Miyahara, a science and engineering associate professor Hiroshima University and one of the study’s co-authors.

Miyahara and colleagues spotted Ryugu’s djerfisherite while using field-emission transmission electron microscopy (FE-TEM) to better understand how terrestrial weathering affected the asteroid’s mineral layers. According to Miyahara, the discovery “challenges the notion that Ryugu is compositionally uniform” and opens new questions about primitive asteroid evolution.

Experts know from past experiments that djerfisherite can be created when potassium-rich fluids and iron-nickel sulfides interact at temperatures over 662 degrees Fahrenheit. Given their understanding of enstatite chondrites, this led Miyahara’s team to two potential explanations.

“The discovery of djerfisherite in a Ryugu grain suggests that materials with very different formation histories may have mixed early in the solar system’s evolution, or that Ryugu experienced localized, chemically heterogeneous conditions not previously recognized,” explained Miyahara.

Early evidence suggests the latter theory is more likely, but researchers can’t be sure solely based on the currently available information. Regardless, the discovery revealed that the solar system’s earliest eras hosted some unexpected deep space interactions. Moving forward, the team hopes to conduct isotopic studies on the samples to narrow down the minerals’ origins. Meanwhile, the sample’s delivery probe Hayabusa2 is currently en route for a 2031 rendezvous with its next asteroid—a small, rapidly spinning rock known as 1998 KY.

The post Deep space asteroid sample contains unexpected ingredient appeared first on Popular Science.

Microsoft, like most other major tech companies, is cramming as much artificial intelligence as it can into its products. It’s shown up in Microsoft Edge, in the Office suite, and even in the most basic programs on the operating system, such as Notepad and Paint.

It’s difficult to get away from, but you’re not obliged to use it. If you’d rather you didn’t have AI assistants regularly interrupting you, or you want to rely on your own abilities to put one word in front of another, there are ways of disabling and hiding the AI.

The steps below apply to a Copilot+ PC (with special AI capabilities), running Windows 11 Home. You may not see exactly the same features and options, depending on the age of your computer and the version of Windows you’re running, but broadly speaking a lot of the settings should be similar.

Windows PCs now come with Copilot preinstalled: You might even find there’s a dedicated Copilot button on your keyboard. Copilot works like Google Gemini or ChatGPT, ready to respond to queries, brainstorm ideas, and help you with other everyday tasks—but if you don’t need it, you can get rid of it.

You can hide Copilot by right-clicking on its icon on the taskbar and choosing Unpin from taskbar, and its shortcut will disappear. Further options can be found in the Copilot app, by clicking on your Microsoft account picture (bottom left) and choosing Settings (click the side panel button, top left, if you can’t see your avatar).

Once you’re into the Copilot Settings page, you’ll see you can turn off Auto start on log in to make sure Copilot doesn’t start up at the same time Windows does. There’s another toggle switch here, Open Copilot using Alt+Spacebar shortcut, which you can disable so you don’t accidentally open the AI assistant using your keyboard.

If you prefer a tougher approach, you can uninstall Copilot just like most of the other programs on Windows. Open the main Settings panel, then choose Apps > Installed apps to see a full list of the apps on your system: Scroll down to Copilot, click the three dots to the right of its entry, and pick Uninstall.

You’ll also find a lot of AI by default in the Microsoft Edge browser. One way of getting away from this would be to switch to a different browser entirely—even if they’re all gradually adding more and more AI features—but you can carry on using Edge as your browser of choice with less AI, should you want to.

With Microsoft Edge open, click the three dots up in the top right corner, then choose Settings. Switch to the Copilot and sidebar screen using the links on the left, then click Copilot. You’ll be able to turn off the Show Copilot button on the toolbar toggle switch so the icon gets hidden from the Edge interface.

There are plenty of other AI features spread throughout Windows, some with the Copilot branding and some without. There’s the Windows Recall feature, for example, which uses AI to track all the activities happening on your PC so you can search back through them—like a browsing history but for your entire computer.

It’s worth mentioning that Windows Recall should be turned off by default on new Windows computers, so you’ll only need to disable it if you’ve previously enabled it. You can check the status of Recall by heading to Windows Settings: Choose Privacy & security > Recall & snapshots, and you’re able to disable the feature if you need to.

Also on the Privacy & security screen, you’ve got another feature called Click to Do, which lets you right-click on text and images to process them via AI and perform various tasks (like web searches). Again, this can be disabled with a toggle switch if you don’t want to use it.

You might have noticed AI creeping into Notepad and Paint too, to help with your writing and image creation—and the features again come via buttons on the toolbars with Copilot branding. In Notepad, click the cog icon (top right) to access the program settings, then turn off the Copilot toggle switch to hide the AI features from view.

Unfortunately, at the time of writing, there’s no similar feature in the Paint program settings screen—you’re stuck with the Copilot button on your toolbar, even if you uninstall the main Copilot app from Windows. It has previously been possible to remove Copilot from Paint in earlier iterations of the app, so this functionality may eventually return.

Microsoft is almost certain to keep pushing out these AI features and extras, and adding them on top of its existing software. But whatever changes come along, keep checking in the system and app options for the ability to remove or disable the AI—the planet will thank you.

The post How to turn off AI in Windows and bring yourself some peace appeared first on Popular Science.

A deadly fungus linked to deaths in archaeologists excavating ancient tombs has been turned into a new cancer-fighting compound. A team at the University of Pennsylvania modified some of the chemicals in the toxic crop fungus Aspergillus flavus, aka the “pharaohs’ curse” fungus, and created a new compound that kills leukemia cells. The findings are detailed in a study published June 23 in the journal Nature Chemical Biology and are an important step towards discovering new fungal medicines for cancer.

“Fungi gave us penicillin,” said Sherry Gao, a study co-author and UPenn chemical and biomolecular engineer, said in a statement. “These results show that many more medicines derived from natural products remain to be found.”

Aspergillus flavus is one of the most frequently isolated mold species in both agriculture and medicine. It is commonly found in soil and can infect a broad range of important agricultural crops. The toxins in this fungus can lead to lung infections, especially in those with compromised immune systems. It is named for its dangerous yellow spores and has been considered a microbial villain for at least a century. 

In the 1920s, after a team of archaeologists opened King Tutankhamun’s tomb near Luxor, Egypt, a series of untimely deaths occurred among the excavation team. Rumors swirled of some kind of pharoah’s curse. Doctors later theorized that fungal spores that had been dormant for thousands of years might have played a role in the deaths. 

During excavations In the 1970s, a dozen scientists entered the tomb of Casimir IV in Poland. Within only a few weeks, 10 of the researchers died. Investigations later revealed the tomb contained the fungus A. flavus. 

The same deadly fungus is now being looked at as a potential cancer treatment. The therapy detailed in this new study is a class of ribosomally synthesized and post-translationally modified peptides, or RiPPs. The name “RiPP” refers to how the compound is produced. It starts in the ribosome–a small cellular structure that makes proteins–and is later modified by peptides or intervention in the lab. In this case, the RiPP is altered to enhance its cancer-killing properties.

“Purifying these chemicals is difficult,” said study co-author and UPenn doctoral fellow Qiuyue Nie. 

While thousands of RiPPs have previously been identified in bacteria, only a handful have been discovered in fungi. One reason for fewer fungal RiPP finds is because past researchers likely misidentified fungal RiPPs as non-ribosomal peptides and did not quite understand how fungi created the molecules. 

“The synthesis of these compounds is complicated,” adds Nie. “But that’s also what gives them this remarkable bioactivity.”

[ Related: College student discovers mysterious fungus that eluded LSD’s inventor. ]

To find more fungal RiPPs, the team first scanned a dozen strains of different Aspergillus fungi. By comparing the chemicals produced by these strains with known RiPP building blocks, the team identified A. flavus as a promising candidate for additional study.

The genetic analysis pointed to a particular protein in A. flavus as a source of fungal RiPPs. When the team turned off the genes that create that protein, the chemical markers that indicated the presence of these RiPPs also vanished. Combining both metabolic and genetic information pinpointed the source of the useful fungal RiPPs in A. flavus and could be used to find other fungal RiPPs in the future.

The team then purified four different RiPPs. They found that the molecules all shared a unique structure of interlocking rings. The researchers named these previously undescribed molecules after the fungus in which they were found: asperigimycins.

Even without genetic modifications, the asperigimycins demonstrated medical potential when mixed together with human cancer cells. Two out of the four variants had potent effects against leukemia cells.

The researchers added a fatty molecule called a lipid to another variant and found that it performed as well as cytarabine and daunorubicin, two FDA-approved drugs that have been used to treat leukemia for decades.

Next, the team wanted to understand why the lipids enhanced asperigimycins’ potency. To do this, the researchers selectively turned genes on and off in the leukemia cells. One gene (SLC46A3), proved critical in allowing asperigimycins to enter leukemia cells in the right amount. That SLC46A3 gene helps materials exit lysosomes, or tiny sacs that collect foreign materials entering human cells. 

“This gene acts like a gateway,” said Nie. “It doesn’t just help asperigimycins get into cells, it may also enable other ‘cyclic peptides’ to do the same.”

Those chemicals have medicinal properties just like asperigimycins. Nearly 24 cyclic peptides have received clinical approval since 2000 to treat diseases from cancer and lupus, but many of them need modification in order to enter cells in sufficient quantities.

“Knowing that lipids can affect how this gene transports chemicals into cells gives us another tool for drug development,” said Nie.

Further experimentation showed that asperigimycins likely disrupt the process of cell division. 

“Cancer cells divide uncontrollably,” said Gao. “These compounds block the formation of microtubules, which are essential for cell division.”

The compounds had little to no effect on breast, liver, or lung cancer cells or on a range of bacteria and fungi. According to the team, this suggests that asperigimycins’ disruptive effects are specific to certain types of cells, which is a critical feature for any future medication.

In addition to showing that asperigimycins do have some future medical potential, the team pinpointed similar clusters of genes in other fungi. This means even more fungal RiPPS could be out there. 

“Even though only a few have been found, almost all of them have strong bioactivity,” says Nie. “This is an unexplored region with tremendous potential.”

The next step towards potentially becoming a therapeutic, asperigimycins need to be tested in animal models, with the hope of one day moving into regulated human clinical trials. 

“Nature has given us this incredible pharmacy,” says Gao. “It’s up to us to uncover its secrets. As engineers, we’re excited to keep exploring, learning from nature and using that knowledge to design better solutions.”

The post Deadly ‘pharaoh’s curse fungus’ could be used to fight cancer appeared first on Popular Science.

Microsoft Office is the industry standard for a reason: apps like Word, Excel, Outlook, and PowerPoint make things like composing documents, organizing and tracking data, handling email, and making presentations easier, faster, and more shareable. It’s easy to pay handsomely for that convenience: Ongoing access to Microsoft 365 can cost more than $120 a year for a family (more if you pay monthly). But right now, you can get lifetime access to the Microsoft Office 2019 suite of applications for just $29.97, 86 percent off the $229 regular price—paid once and never again.

With this offer, you get Microsoft Office Professional Plus 2019 for Windows—a productivity suite that includes word processing with Word, data management with Excel, email capability from Outlook, presentation creation from PowerPoint, desktop publishing with Publisher, database management in Access, and the digital notetaking of OneNote. (Worth noting: This deal does not include video conference and messaging program Microsoft Teams.)

What makes it so cheap? Microsoft Office 2019 isn’t the latest version of the Office suite (that would be Office 2024, or the subscription-based Microsoft 365), so it doesn’t have some of the most recent features like AI capabilities, the newest user interface, and more robust recording capabilities for PowerPoint and data analysis in Excel. However, it does include Publisher (which isn’t included in Office 2024), and has all the reliable performance and options you’re used to in Office programs to keep your business and home running.

With this deal, you’re getting lifetime access—including future updates and free customer support—to the entire Microsoft Office 2019 suite from an authorized Microsoft partner, so you can feel confident in your purchase. It’s good for installation on one Windows PC. (This license will be connected to the device you install it on, not your Microsoft account.) You’ll get the links and software license keys immediately in your email; just make sure to download your copy within 7 days.

You already have too many subscriptions—this is your chance to break the cycle. Take advantage of this low pricing and unlimited use of Word, Excel, PowerPoint, and Excel are yours, with no more recurring payments.

Get Microsoft Office Professional Plus 2019 with access to Word, Excel, Outlook, and more for $29.97 (reg. $229).

StackSocial prices subject to change.

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Microsoft Office Professional Plus 2019 for Windows

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The post Get all the power of MS Office for life—and for less than $30 appeared first on Popular Science.

This article was originally featured on The Conversation.

People have been celebrating the summer solstice with elaborate rituals since prehistoric times. But humans aren’t the only species to take mark June 21 as a special time. Studies are showing the summer solstice is an important cue for plants too.

Recent studies, including one of my own, have proposed that trees may use the longest day of the year as a key marker for their growth and reproductive cycles. The solstice seems to act like a calendar reminder for trees.

For example, at the solstice, trees growing in cold places slow down the creation of new wood cells and focus their energy on finishing already formed but still incomplete cells. This ensures trees have time to complete cell construction before winter hits. Incomplete cells are damaged by freezing winter temperatures, rendering them useless for water transport the following year.

Along similar lines, trees use the solstice to fine-tune the “winding down”, or senescence, of their leaves in preparation for autumn. Senescence allows the tree to reabsorb critical nutrients from the leaves before they fall. This process is timed to balance missing out on sunlight from “winding down” too early, against leaving it too late and losing nutrients if still-green leaves are killed by autumn frosts.

Satellite observations of forests, and controlled experiments in greenhouses, reveal that warmer temperatures immediately prior to the solstice cause the onset of leaf browning to start earlier that autumn. In contrast, warmer temperatures just after the solstice slow down the senescence process.

This means a longer transition period from green to fully brown leaves. This fine-tuning enables trees to extend the period of photosynthesis in years when temperatures stay warmer for longer, so they don’t miss out on these favourable conditions.

But not all scientists are convinced. From an evolutionary perspective, the solstice may not be the best seasonal marker for timing these transitions. For example, in forests in the far north, leaves do not appear until early June, only days before the solstice, and the growing season can extend late into October. In these forests, using the solstice to initiate the winding down process makes little sense for trees that have only just started growing for the year.

Nevertheless, there is more consensus about plants using the solstice to synchronise reproduction.

In many plants, especially trees from the temperate mid-latitudes, the number of seeds they produce varies dramatically year on year, known as masting. A large European beech tree can produce hundreds of thousands of seeds in a bumper year (a “mast event”) and forgo reproduction altogether in other years.

Beech trees vary their annual seed production in step, often on a continental scale. They do this to increase the efficiency of their reproduction.

A small moth, Cydia fagiglandana, lays its eggs in beech flowers. When the grubs hatch, they eat and destroy the developing seeds. Cycles of famine and bumper years help protect their seeds from these moths.

UK beech trees typically lose less than 5% of their seeds to Cydia because the cycles starve the moths into low numbers ready for masting years. But when trees are out of sync, seed loss can increase to over 40%.

For decades we have known that beech mast events happen in the year after a warm summer. These warmer temperatures trigger an increase in the formation of flower buds. More flower buds usually lead to a greater crop of seeds that autumn.

Scientists have long puzzled over how beech trees across Europe seem to use the same seasonal window to control mast events. Their seed production is determined by temperatures in late June and early July, irrespective of where they grow in Europe. But how can a beech tree know the date?

In my team’s 2024 study, we showed that they use the solstice as a seasonal marker. As soon as the days start to shorten after the solstice, beech trees across Europe seem to simultaneously sense the temperature.

Anywhere temperatures are above average in the weeks following the solstice can expect to have a mast event the next year. Weather conditions in the weeks before the solstice, by contrast, seem to be irrelevant. As seen on weather maps, warm and cool spells tend to occur simultaneously over large areas.

This allows beech trees to maximise the synchrony of their reproduction, whether that is investing in a mast year (warm temperatures), or forgoing reproduction for a year (low temperatures). Using a fixed marker like the solstice is the key to achieving this synchrony, and the benefits that come from it.

The evidence for this phenomenon has come from observations across dozens of forests across Europe. However, my research group is collaborating with about a dozen other groups in Europe to test this effect by manipulating the temperature of beech branches before and after the solstice at different sites. Ongoing research I am involved with seems to show flowering genes are activated at the summer solstice.

Also, studies into the circadian rhythms of plants show they have mechanisms in their molecules that allow them to detect and respond to tiny changes in day length. This is the basis for that extraordinary scale of synchronised reproduction.

If the weather is warm over the next month or so, then there is a good chance that beech trees in your local area will have heavy seed crops next autumn. What’s more, trees across the UK and into northern and central Europe will probably be doing the same.

The post Could trees know when the summer solstice is? appeared first on Popular Science.

When it comes to selecting a pair of sunglasses, most people choose style over substance. But depending on the activities you’re planning, you may want to offer more consideration to the tint (color) and shade (darkness) of your sunglasses. Because while colored lenses can be fun, they’re also functional. The right ones can reduce glare and brightness, but also boost color perception and clarity, depending on the weather conditions and circumstances. 

So this summer, choose wisely to protect your eyes, enjoy your surroundings, and maintain good vision whether you’re lounging by the beach or summiting mountains.

Before you start obsessing over the color of your lenses, put the safety of your eyes first. When picking sunglasses insist on ones with 100 percent UVA and UVB protection, says Emily Schehlein, ophthalmologist at Brighton Vision Center in Michigan and spokesperson for the American Academy of Ophthalmology. 

[Related: The evolution of sunglasses from science to style (and back again)]

UV light can cause eye cancer, cataracts, pterygium or surfer’s eye—a growth from the corner of your eye to your cornea that can affect people of any age—and a slew of other conditions that could put your vision and overall health at risk. Fortunately, she says, “Sunglasses can help cut down on the risk of those diseases.”

The bigger the lenses, the better, she adds, highlighting that contact lens wearers–most contacts are UV protective–should wear sunnies, too, to protect their whole eyes. Schehlein advises that you wear sunglasses any time you’re outdoors, especially in the summer when UV is three times stronger, on the beach, on water or snow when reflective light is bouncing in every direction, and when on medications that can cause photosensitivity.

When it comes to selecting the perfect pair of sunnies, the color of the lens can matter more than you think. Different lens tints can filter light and change our perception in various ways.

That said, yellow and amber are the only colors scientifically proven to notably boost contrast sensitivity by filtering out shorter wavelengths of light, giving the perception that vision is clearer. Yellow (and pink) is a solid option in low light, including around dusk and on overcast days.

Other colors may still offer a visual boost or more comfort depending on the conditions, says Marcus Franck, co-founder of Vallon, a sunglasses brand with a focus on optical clarity in sports lenses.

For example, Franck says most Vallon sunglasses are fitted with tints like grey, brown and green, which offer natural color vision and excellent light-blocking on bright, sunny days. They tend to be the most popular shades for everything from mixed-light conditions like when hiking in and out of woods, to full sun. If you’re only going to have one pair of sunglasses, grey or brown are a good choice.

Grey is best at reducing brightness in extremely sunny conditions and offers the most accurate color perception. Brown lenses can ease eye strain and offer better focus and more comfort in the long run, according to Franck. Plus they help maintain depth perception. They don’t work as well on rainy or overcast days, though.

So if you’re enjoying a sunny beach day or watching your kid’s summer soccer game, stick with brown or grey, which will provide protection and strain-free vision. If you’re golfing, mountain biking, or hiking, brown or yellow tints can help with visual acuity (sharp vision) and depth perception, even in overcast conditions.

Finishes can also affect how our eyes perceive our surroundings. For example, mirror finishes that add a reflective shine to the outside of sunnies aren’t just for looks. The thin layer of metallic coating cuts down on the amount of visible light entering eyes and can even boost UV protection, making them an excellent choice for bright, sunny days.

Likewise, polarization is a chemically applied filter that blocks horizontal light—reflections on flat surfaces like water or the road—which is what our eyes see as glare. Think of polarization like blinds on a window, Schehlein explains: Light still passes through partially open blinds, but there’s less of it and it’s mostly coming from one direction. This effectively darkens your field of vision and reduces glare by eliminating bouncing light. Polarized coatings are excellent for driving or when you’re on a body of water when reflections can make details harder to decipher.

However, Franck says, “Polarization actually makes it harder for our eyes to safely distinguish between layers of snow and ice. So for skiing, ski touring, snowboarding and high altitude mountaineering on ice, non-polarized lenses are better.”

Higher quality glasses may be advertised as in a category from 1 to 4. These categories are determined by how much light passes through the lens to your eye via a metric called VLT (Visible Light Transmission). The higher the category, the darker the lens. If you see a VLT percentage, it’s the opposite: the smaller the number, the less light is passing through the tinted lens.

The darkest sunglasses are category 4 or have a VLT percentage between three to seven, according to Vallon’s website. Category 1 indicates lenses with a VLT between 46 to 79 percent, or lightly tinted. The key is to find a balance between too light and too dark. “A very dark tint may negatively impact visual clarity/acuity,” says Schehlein. But go too light and you may not see as much glare reduction and eye fatigue may increase depending on the conditions. “The ideal tinted lens gives a balance between improving contrast and reducing glare/light scatter but maximizing visual acuity.”

So choose your lens color wisely, then enjoy less eye strain and better contrast and protect your eyes when you’re outdoors.

The post How to protect your eyes with the right sunglass tint appeared first on Popular Science.

Smartphones have usurped many of the gadgets and devices we used to carry and rely on. But, there are some things they can’t do. Coast makes practical gear, including flashlights, multitools, headlamps, and more. Right now, you can get 30 percent off of anything on the site if you use the code: FATHERSDAY30 during checkout. Yes, Father’s Day is over, but this sale goes through June 30th, so there’s still time.

Coast

A reliable multitool will come in handy way more than you expect. This model measures just 3.85 inches long and includes a total of 15 useful tools. The spring-loaded mechanism allows you to open the pliers with a one-handed motion and there’s even a built-in LED flashlight to help you see what you’re doing. It’s made of durable stainless steel and comes with a limited lifetime warranty. That’s a ridiculous deal for $28.

Coast

Sometimes the smartphone flashlight just doesn’t provide the light you need. This super-compact penlight maxes out at 280 lumens, which is well beyond what a typical phone LED can put out. The rotating lens allows you to focus the beam depending on whether you want a concentrated spot or a wider glow. It’s dust-resistant and built rugged so it can take a beating in your pocket all day.

Coast

This is one of the sleekest pocket knives I have ever seen. It has a 2.85-inch set into a stonewashed titanium handle. It opens smoothly and quickly with a simple flipper tab and locks tightly so it won’t deploy in your pocket.

Coast

This is an extremely versatile light to take camping or keep on-hand for emergencies. The built-in battery stores enough juice for up to 10 hours of operation depending on the settings and conditions. It can output up to 3,000 lumens of light and offers both solid and flashing modes to help signal for help.

• Coast F401 1919 Reserve Limited Edition fixed blade knife $35 (was $50)
• Coast 1919 Reserve Limited Edition RX357 Folding Knife $28 (was $40)
• Coast Dual LED 155 Multi Tool $35 (was $50)
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• Coast Beamsaver Memory Mode flashlight $56 (was $80)
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The post Save 30% on flashlights, multitools, headlamps, and EDC essentials during Coast’s sitewide sale appeared first on Popular Science.

Construction workers digging about four miles north of Aarhus, Denmark have accidentally discovered a “spectacular” Viking gravesite. Dating back to the second half of the 10th century, the archeological trove may even tie directly to one of Denmark’s most famous rulers: King Harald “Bluetooth” Gormsson. And yes—his legacy is tied to the handy wireless feature in your smartphone.

The roughly 30 graves containing artifacts and treasures represent the era’s entire social hierarchy spectrum, according to an announcement by the Moesgaard Museum. The findings include a gold-threaded box, pearls, coins, ceramics, and even a pair of scissors likely owned by an important noblewoman of the time. The box itself is a particularly remarkable find, as experts believe it’s only the third confirmed example of its kind. Human remains such as bones and teeth were also found at the site along with smaller, less ornate graves that possibly held an elite family’s enslaved workers.

“Together, they paint the picture of an aristocratic environment that was linked to royal power, and which was part of the Vikings’ vast and dynamic world,” Kasper Andersen, a Viking Age historian at Moesgaard, said in a statement.

Archeologists speculate the burial site is probably related to a nobleman’s farm located less than 0.65 miles away. That find, discovered in the 1980s, may have belonged to an earl or steward of King Harald Bluetooth—a legendary figure in his own right.

The son of King Gorm the Old, Harald ruled over Denmark and Norway from around 958–986 CE and allegedly earned his nickname from a conspicuously colored tooth. More importantly, he is remembered for spreading Christianity across Denmark, as well as consolidating power over the regions of Jutland and Zealand.

Bluetooth’s cultural and territorial influence is famously symbolized by the Jelling Stone—a large rune stone erected in its namesake town by the king in 965 CE. The monument served to commemorate his parents and list his accomplishments, and is often referred to as “Denmark’s Birth Certificate.” More recent archeological evidence, however, indicates Bluetooth probably didn’t introduce Christianity to his kingdom, as much as formalize its recognition amid shifting cultural tides.

Despite this, King Harald’s push for unification has remained a focal point in Scandinavian history. His influence is so prominent that during the 1990s, Swedish telecom giant Ericsson picked “Bluetooth” as the working name for a technology intended to “unite” the computer and cellular service industries. The moniker ended up sticking, and the Ericsson T39 cellphone is credited as the first phone to feature Bluetooth connectivity upon its release in 2001.

Its recognizable icon still used today? The Nordic rune for “B,” also featured prominently on King Bluetooth’s Jelling Stone. And, possibly, some of the archeological relics excavated at the burial site. Experts intend to finish excavations this month, after which they’ll begin detailed analysis work on their finds.

The post Construction workers find Viking graves linked to King ‘Bluetooth’ appeared first on Popular Science.