If you were asked to picture how electrons move, you could be forgiven for imagining a stream of particles sluicing down a wire like water rushing through a pipe. After all, we often describe electrons as “flowing” in an “electric current.”

In reality, water and electricity flow in completely different ways. Whereas water molecules move together to form a swirly, coherent substance, electrons tend to fly past one another. “Water is seeing nothing but other water,” said Cory Dean, a physicist at Columbia University, “but in an electronic system, in a wire, that’s manifestly not the case.” Water molecules unite to flow, but each electron acts on its own.

This every-particle-for-itself movement serves as the foundation for all of electronic theory. It explains why a warm wire resists more than a cold wire, and why a round wire conducts as well as a square wire.

But since the 1960s, theorists have suspected that electrons can be coaxed to act more like their watery counterparts, and to form an electron fluid.

In recent years, a string of experiments has confirmed that prediction. Last fall, in the most dramatic demonstration yet, Dean and his collaborators arranged for electrons to form a type of shock wave that occurs when a quickly flowing fluid crashes into a slowly flowing fluid. It was a surefire sign that electrons were flowing at extremely high speeds. “That’s really the frontier right now,” said Thomas Scaffidi, a physicist at the University of California, Irvine who was not involved in the experiment.

Sending a mission to the solar gravitational lens (SGL) is the most effective way of actually directly imaging a potentially habitable planet, as well as its atmosphere, and even possibly some of its cities. But, the SGL is somewhere around 650–900 AU away, making it almost four times farther than even Voyager 1 has traveled—and that's the farthest anything human has made it so far.

It will take Voyager 1 another 130+ years to reach the SGL, so obviously traditional propulsion methods won't work to get any reasonably sized craft there in any reasonable timeframe. A new paper by an SGL mission's most vocal proponent, Dr. Slava Turyshev of NASA's Jet Propulsion Laboratory, walks through the different types of propulsion methods that might eventually get us there—and it looks like we would have a lot of work to do if we plan to do it anytime soon. It is available on the arXiv preprint server.

Carbon dioxide emissions from China have flatlined or fallen for 21 months, meaning the world's biggest greenhouse gas emitter may have reached a global turning point sooner than expected.

China's carbon dioxide (CO2) emissions dropped by 1% in the last quarter of 2025 and likely by 0.3% over the whole year, keeping them just beneath the record highs reached in May 2024, according to a new analysis by the Finland-based Centre for Research on Energy and Clean Air (CREA) for Carbon Brief. The nearly two-year flatline or fall is the longest on record not driven by an economic slowdown in the country, which emits over a third of global CO2.

If the trend holds, China's emissions could reach an all-time peak before 2030 — the country's official target date — or even sooner, marking a key win in the global effort to curb fossil fuel use and slow global warming. Yet whether the drop is sustained or demand will drive a rebound in emissions before the officially targeted peak remains an open question.

The Trump administration on Thursday revoked a scientific finding that long has been the central basis for U.S. action to regulate greenhouse gas emissions and fight climate change, the most aggressive move by the president to roll back climate regulations.

The rule finalized by the Environmental Protection Agency rescinds a 2009 government declaration known as the endangerment finding that determined that carbon dioxide and other greenhouse gases endanger public health and welfare.

The endangerment finding by the Obama administration is the legal underpinning of nearly all climate regulations under the Clean Air Act for motor vehicles, power plants and other pollution sources that are heating the planet.

President Donald Trump called the move "the single largest deregulatory action in American history," while EPA Administrator Lee Zeldin called the endangerment finding "the Holy Grail of federal regulatory overreach."

EPA has a clear scientific and legal obligation to regulate greenhouse gases, McCarthy said, adding that evidence backing up the endangerment finding "has only grown stronger" as the health and environmental hazards of climate change have "become impossible to ignore."

A kidney transplant can be life-changing, but it usually comes with a lifelong tradeoff: daily immunosuppressant pills that keep the immune system from attacking the donated organ.

A new study suggests there may be another path in the future, one that could reduce the daily medication burden to a monthly treatment. Researchers say the goal is not just convenience. The approach could also limit side effects and help donor kidneys keep working longer.

Right now, most kidney transplant recipients take several drugs every day to prevent rejection. While these standard immunosuppressants protect the new kidney, they can gradually harm kidney function and may lose effectiveness over time.

Hatches open! Four SpaceX Crew-12 crew members have entered the station and joined Expedition 74 to begin a long-duration space research mission. More... go.nasa.gov/4twQhDf

Ancient Egyptian mummies have a distinctive odor known only to those who've gotten close enough for a sniff. Now, scientists have captured these invisible vapors to find clues about the way they were embalmed.

Usually, archeologists take a more invasive approach to mummy analysis by cutting away a piece of bandage and dissolving it to get a read on the molecular makeup of embalming agents.

But this process is inherently destructive. Sometimes the molecules fall apart in the process. And there are only so many pieces of bandage you can take before the entire mummy unravels.

Instead, a team of organic geochemists from the University of Bristol realized they could sample volatile organic compounds (VOCs) from the air surrounding the mummy. VOCs are molecules that rise readily from their source and spread through the air, hitting your nostrils with their unique scent signatures.

In a set of carefully designed experiments modeled on children’s tea parties, researchers at Johns Hopkins University found that an ape could engage in pretend play. The results mark the first controlled demonstration that an ape can imagine objects that are not actually there, a skill long considered uniquely human.

Across three separate tests, the bonobo interacted with invisible juice and imaginary grapes in a consistent and reliable way. The performance challenges longstanding assumptions about the limits of animal cognition.

The researchers conclude that the ability to understand pretend objects falls within the mental capacities of at least one enculturated ape. They suggest this ability could trace back 6 to 9 million years to a common ancestor shared by humans and other apes.

Ape Imagination Upends Human Uniqueness in Science Study
“It really is game-changing that their mental lives go beyond the here and now,” said co-author Christopher Krupenye, a Johns Hopkins assistant professor in the Department of Psychological and Brain Sciences who studies how animals think. “Imagination has long been seen as a critical element of what it is to be human, but the idea that it may not be exclusive to our species is really transformative.

“Jane Goodall discovered that chimps make tools, and that led to a change in the definition of what it means to be human, and this, too, really invites us to reconsider what makes us special and what mental life is out there among other creatures.”

The musk oxen’s strength lies in their unity, but even the tightest herd can be broken by a relentless pack of Arctic wolves.

A new study from U of T Scarborough suggests that mental sharpness is not just a feeling. When people’s thinking is clearer and more efficient, their daily output can look like they added roughly 40 extra minutes of productive work.

The research, published in Science Advances, followed people for 12 weeks and focused on changes within the same individual over time, not differences between individuals. That design matters because it helps separate temporary mental states from more stable qualities such as baseline ability or personality. The team found that everyday swings in sharpness helped explain why someone might confidently plan their day and then struggle to act on it.

“Some days everything just clicks, and on other days it feels like you’re pushing through fog,” says Cendri Hutcherson, associate professor in the Department of Psychology at U of T Scarborough and lead author of the study.

“What we wanted to understand was why that happens, and how much those mental ups and downs actually matter.”

What Researchers Mean by Mental Sharpness
In this study, mental sharpness refers to how efficiently the brain is operating in the moment. It reflects how readily someone can keep attention on track, make choices, set targets, and then follow through. When that system is running well, tasks can feel straightforward. When it is not, even basic steps can start to drag.

Going to space is harsh on the human body, and as a new study from our research team finds, the brain shifts upward and backward and deforms inside the skull after spaceflight.

The extent of these changes was greater for those who spent longer in space. As NASA plans longer space missions, and space travel expands beyond professional astronauts, these findings will become more relevant.

Why it matters
On Earth, gravity constantly pulls fluids in your body and your brain toward the center of the Earth. In space, that force disappears. Body fluids shift toward the head, which gives astronauts a puffy face. Under normal gravity, the brain, cerebrospinal fluid and surrounding tissues reach a stable balance. In microgravity, that balance changes.

The International Space Station returned to full strength with Saturday's arrival of four new astronauts to replace colleagues who bailed early because of health concerns.

SpaceX delivered the U.S., French and Russian astronauts a day after launching them from Cape Canaveral.

Last month's medical evacuation was NASA's first in 65 years of human spaceflight. One of four astronauts launched by SpaceX last summer suffered what officials described as a serious health issue, prompting their hasty return. That left only three crew members to keep the place running—one American and two Russians—prompting NASA to pause spacewalks and trim research.

Moving in for eight to nine months are NASA's Jessica Meir and Jack Hathaway, France's Sophie Adenot and Russia's Andrei Fedyaev. Meir, a marine biologist, and Fedyaev, a former military pilot, have lived up there before. During her first station visit in 2019, Meir took part in the first all-female spacewalk.

This video of cornflower root hairs, captured by Wim van Egmond, shows the single-cell extensions on the cornflower's roots. See more from the microscopic world: on.natgeo.com/4qyGUQR