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Can you slip into a more relaxed state and sharpen your focus by simply listening to a couple of slightly different tones? That’s the idea behind binaural beats, an auditory phenomenon that’s increasingly getting headlines as a cure for procrastination and everyday stress. 

The idea of binaural beats is hardly new. Heinrich Wilhelm Dove, a physicist and meteorologist, first recorded the phenomenon in 1839. But, nearly 190 years later, scientists are still exploring what they are and what they can and can’t do, Bopanna Ballachanda, past president of the American Academy of Audiology and an expert in auditory neuroscience, tells Popular Science. Here’s what binaural beats are, and what the science says about their effectiveness.

Sounds are measured by their frequency in hertz, which counts how many times a sound wave vibrates per second. Low tones have low frequencies and a lower hertz value, while high tones have high frequencies and a higher hertz value.  

A binaural beat occurs when two tones with different frequencies are played in each ear, producing a third phantom tone, or binaural beat. The frequency of that third beat is the gap in the frequencies between the two separate tones. 

So, if you play a 400-hertz tone in the right ear and a 404-hertz tone in the left ear, the brain perceives an imaginary binaural beat of four hertz, Ballachanda says. “That difference in the frequency of sound creates an image in the brain as a beat, the basis of the binaural beats.” 

In short, binaural beats are auditory illusions your brain creates when it hears different tones in each ear. But be sure you’re wearing headphones (perhaps these or these), or else you won’t hear that phantom binaural beat.

When a brain creates an imaginary binaural beat, some researchers believe it could lead to “brain entrainment.” The brainwave entrainment hypothesis, as a 2023 systematic review explains, suggests that when the brain is exposed to a binaural beat, the brain’s electrical activity syncs up to that frequency.

Specific frequencies have been connected to different emotions or cognitive abilities. For example, researchers have found delta brainwaves, measured at 0.5 to four hertz, are linked to deep sleep and pain relief. Theta waves, measured at four to seven hertz, can help with deep relaxation. Alpha waves, measured at eight to 12 hertz, are associated with learning. 

Binaural beats can be perceived from about one to 30 hertz, the systematic review says. So syncing up our brains to a binaural beat that generates a relaxing frequency could allow us to manipulate our brains to chill out a bit. But the jury is still out on whether binaural beats trigger brainwave entrainment, according to the review. Among the 14 studies reviewed, five supported the idea, eight contradicted it, and one ended with mixed results. 

The science also is still very much evolving on the actual impact of binaural beats to our mood and cognitive abilities, Ballachanda says. 

Some studies show promising results. A 2018 meta-analysis of 22 studies, for example, found that the beats can boost cognition, including memory and attention, and reduce anxiety and pain. The effectiveness, researchers found, depends on the frequency used, the time under exposure and the moment when the exposure took place. 

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In a 2020 study, participants who combined psychiatric treatment with binaural beat meditation had larger reductions in anxiety compared to those who used only binaural beats or psychiatric care. 

Then in a 2025 study, 80 undergraduate students listened to both control sounds and binaural beats. The study found that specific binaural beats with a low tone and white nose improved general attention but didn’t stop focus from eventually fading. The results confirmed brain entrainment, but it varied with the binaural beat and background noise. 

But not every study shows positive effects. One 2023 study of 1,000 people found that listening to binaural beats at home while taking a test reduced their performance, while silence or listening to other sounds had no impact. 

If you want to give binaural beats a try, there’s no harm, Ballachanda says, as long as you don’t turn the volume up too loud. “Beats do not cause damage by itself,” he says.

So, if you’re eager to unwind or focus on that big assignment, it could be worth giving binaural beats a shot. Online options on YouTube and elsewhere make it easy to tune in and, possibly, reframe your state of mind.

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 Do binaural beats really help you focus? appeared first on Popular Science.

California has committed $1 billion in annual funding from cap-and-trade revenue to its high-speed rail project, giving CAHSR a crucial financial lifeline.

“The steady funding agreement, formalized under new legislation signed this week, gives the California High-Speed Rail Authority the long-term stability it says is essential to completing the project's initial Merced-to-Bakersfield segment by 2033,” explains Theo Berman in Newsweek.

New legislation signed this week extends California’s cap-and-trade program to 2045 and establishes the appropriation to high-speed rail through the same year. “The authority said the sustained funding would fill the current gap in its business plan and provide a critical match for future federal grant opportunities. It also enables the agency to pursue private-sector partnerships and begin work on trainset procurement and early operations planning.”

To date, 70 miles of track bed and over 50 bridges in the Central Valley segment have been completed, and tracklaying is expected to begin later this year.

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House Republicans are pushing to eliminate some traffic safety measures in Washington, D.C., including traffic enforcement cameras and a ban on right turns on red lights.

As David Meyer explains in Streetsblog USA, “Speed, red light, stop sign, school bus stop-arm and bus priority enforcement cameras have been a longtime bugaboo of the House GOP, whose members pushed a similar provision in 2023 that failed to become law.”

Now, Congress members are using Trump’s federal takeover of D.C. to push more changes, even though data shows speed cameras reduce crashes and injuries. “A 2014 report by the District Department of Transportation and Metropolitan Police Department found injuries and crashes both dropped in the three years after the installation of a new enforcement camera.”

The same lawmakers want to reverse the city’s ban on right turns on red. “Like traffic enforcement cameras, right-on-red bans help make streets safer — in this case by reducing conflicts between turning drivers and pedestrians.”

According to Jeremiah Lowery of D.C's Bike, Walk and Bus PAC, the proposals are “all about feeling. None of it's based on research, none of its based on data.”

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Guide dogs that assist people with blindness or partial sightedness are a powerful reminder of the bond humans have formed with our four-legged companions. Properly trained working dogs serve as a second set of eyes and as a constant, high-stakes assistant, offering an unmatched ability to help their handlers avoid danger and navigate a busy world with confidence.

But guide dogs have limitations. Although it may not be obvious to the casual dog lover, these animals can cause headaches for some owners with disabilities. As living creatures, they require constant care and feeding, responsibilities that some people may not be physically or financially able to manage. And while many people do form strong bonds with their guide dogs, others view them more akin to tools–tools that shed and poop. Well-trained guide dogs can also cost upwards of $50,000 to train, making them inaccessible to many who might otherwise benefit.

That’s why the concept of a robotic “dog” can seem quite appealing. These robotic guide dogs, which have been tested by various universities for years, could offer many of the same benefits as real dogs, without the need for constant care. 

But what should these robot dogs actually look like? That question has been top of mind for a research team at Georgia Tech, which is working to develop an optimal robotic guide dog platform, one that provides both reliability and safety for users, while also fitting into the physical world without drawing unwanted attention. Their proposed solution, outlined in a preprint paper, is a robot that resembles a dog without the cute cuddliness that attracts crowds eager to pet it or take selfies.

“We work with people who use guide dogs, [and] we also understand the challenges and costs of training a guide dog, the challenges of living with a guide dog, and the possibilities for technology to overcome these hurdles,” Georgia Tech School Interactive Computing Professor  Bruce Walker said in an interview shared with Popular Science. “It turns out, we can make more robots than we can dogs.”

“For elderly people, especially with vision loss, it will be easier for them to keep this dog instead of having a real animal dog.” Georgia Tech Computer Science Ph.D Student J. Taery Kim said in an interview shared with Popular Science. “More people will have this opportunity to have their independent mobility than before.

As part of the study, researchers from Georgia Tech’s School of Interactive Computing surveyed blind and partially sighted individuals to understand what they wanted in a robotic guide dog. Overall, respondents expressed a preference for a robot that resembled a dog and appeared approachable in public settings. They also emphasized the importance of clear indicators (such as a vest) to signal that the robot is an assistive device. Other features included built-in GPS, Bluetooth connectivity, and accessible voice commands. Respondents also noted the need for long battery life and the ability for the robot to autonomously dock and recharge.

But respondents were clear that the robot should not be indistinguishable from a real dog. Specifically, they preferred a body texture that is soft but not furry, and emphasized that the robot shouldn’t be so cute that it attracts unwanted attention. In general, participants said they wanted to strike a balance: the robot should resemble a dog enough to blend in, but not so closely that it becomes a spectacle. 

“A lot of people said they didn’t want the dog to look too cute or appealing because it would draw too much attention,” Aviv Cohav, one of the paper’s authors said in a statement.  

Even the most advanced quadruped robot on the market today can’t match a real dog’s innate sense of smell or its highly developed navigational instincts. That said, robotic guide dogs offer other advantages. They don’t need food or veterinary care, and they can be equipped with 360-degree cameras and built-in AI detection systems that scan for cars, debris, and other hazards. Voice recognition capabilities also mean these robots could potentially understand far more commands than even the smartest dog. Built-in SOS functions also allow the robot to detect if a person has fallen and call for help. 

Sure, a real dog can bark for assistance but it can’t dial 911. A robot, unlike a dog, can also talk back.

“The benefit of a robot guide dog is they can do verbal communication unlike an animal dog,” Georgia Tech Assistant professor Sehoon Ha said in a video interview shared with Popular Science. “We hope this robot can connect to large language models [LLMs] and talk to people.” 

Directly asking blind and partially sighted individuals what they want in a robotic guide dog revealed several other preferences. One key concern, according to the researchers, was the need to limit the amount of noise the robot makes. Users need to hear the robot to know it’s functioning, but only to a point. If it’s too loud or sounds overly robotic, it can become disruptive, especially in crowded indoor environments. 

Striking the right balance between meeting the immediate needs of users and blending seamlessly into public spaces is central to the researchers’ work. All of these factors are being taken into account as the researchers work to develop a useful robot dog prototype.

Related: [Can this robot help solve a guide dog shortage?]

The idea of a robotic guide dog isn’t entirely new and actually dates back to Japan in the late 1970s. That early prototype, which failed to achieve commercial success, looked less like a dog and more like a deconstructed refrigerator on a leash. Since then, numerous universities and private companies have attempted to develop a usable version. Just last year, researchers at the University of Glasgow unveiled “RoboGuide,” an AI-powered quadruped robot capable of navigating its surroundings and avoiding obstacles in real time. Researchers at the University of Massachusetts Amherst are working on a similar design. 

Some guide robots are already on the verge of being deployed, though on a limited scale. In China, researchers from Shanghai Jiao Tong University’s School of Mechanical Engineering have begun field-testing a six-legged, English Bulldog–sized robot that can reportedly plan routes and navigate around traffic. The six-leg design was introduced to enhance structural stability. Glidance, a U.S.-based company, has also developed a five-pound, vacuum cleaner–shaped autonomous guide robot called “Glide,” which moves simply by being pushed forward by the user. Glidance CEO Amos Miller, who has personally relied on guide dogs, summed up the potential advantages of robotic alternatives. 

“You get the dog without the responsibility of the dog,” Miller previously told Popular Science, noting the advantage of robotic assistants. 

Though each of these designs holds some promise, they are only truly useful to the people who rely on them if the robots can navigate broader social environments without drawing undue attention. Robots that are startling or distracting, and that confuse or intimidate the average passerby, risk doing more harm than good.

“To have impact, the technologies we produce must be produced with society in mind,” Walker said in a statement. “This is a holistic design that considers the users and all the people with whom the users interact.”

The post The perfect robot guide dog shouldn’t be cute appeared first on Popular Science.

When the biggest geomagnetic storm in 20 years hit Earth in May 2024, photographer Kavan Chay was in Tumbledown Bay, New Zealand. Armed with a Nikon Z 7 astro-modified camera, Chay captured a absolutely spectacular shot (seen above) of the vibrant aurora that resulted from the G5-level storm.

“The aurora pulsed throughout the night, almost like it was alive,” Chay wrote on Instagram. “It was breathtaking to watch and really made all my past week of anxious thoughts quiet. It’s incredible how nature can really help you with these things.” Chay’s image earned top honors in the Aurorae category of the 2025 Royal Observatory Greenwich’s ZWO Astronomy Photographer of the Year.

A spectacular photographer titled “The Andromeda Core” (seen below) by Weitang Liang, Qi Yang, and Chuhong Yu took the Overall Winner prize.

“‘The Andromeda Core’ reveals an astonishing level of detail that truly took my breath away,” Sam Wen, Founder and CEO of ZWO said in a statement. “Achieving such clarity and depth requires not only top-tier astronomical equipment and exceptional seeing conditions, but also a tremendous amount of patience and perseverance. It’s clear that behind this image lies a dedicated team whose persistent effort and collaboration made this masterpiece possible. A brilliant capture of one of our closest galactic neighbours—congratulations on this outstanding achievement!”

The post 18 jaw-dropping images from the 2025 ZWO Astronomy Photographer of the Year awards appeared first on Popular Science.

Interior Secretary Doug Burgum announced the department will seek to reverse a public lands management rule that added conservation as a use of public lands on par with development and extraction,  according to reporting by Matthew Brown for the Associated Press. 

The rule, adopted under the Biden administration in 2024, allowed for public lands to be leased for conservation and restoration in the same way it is leased for extractive uses such as oil drilling. Overturning it, according to Secretary Burgum, “protects our American way of life and gives our communities a voice in the land that they depend on.” Industry representatives say the change will allow the U.S. to exploit its own natural resources. Until the 2024 rule, the agency frequently leased land for grazing and oil and gas leases. 

Environmentalist groups say the rule elevated conservation to its appropriate, “long-neglected” role in the Bureau of Land Management’s mission under the 1976 Federal Lands Policy Management Act. The move adds to a series of changes in federal policy aimed at increasing mining, development, and the sale of public lands.

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