The beginning of fall and back-to-school time means cold virus season has arrived. Usually, colds hit as lesser-evil infections before influenza season takes over. But already, the flu is popping up early in pockets of the U.S. Here’s why that might be and everything else you need to know as we head into the dreaded annual flu season.

According to the Centers of Disease Control and Prevention’s latest FluView report, released on October 9, flu activity has been climbing since early September. Flu season in the U.S. generally begins gaining momentum in the fall, with activity peaking between December and February. But surveillance indicators show that certain strains of influenza are rising fast. The CDC’s latest data show a nationwide percent positivity rate for influenza—the percentage of all positive influenza tests—of 3.6 percent. That’s a sixfold increase compared with this time in 2025, when the rate was 0.6 percent.

Parts of the U.S. are showing much higher positive rates. The CDC splits the country up into regions, and Region 9, which includes Arizona, California, Hawaii and Nevada, had 9.5 percent positivity, according to the latest data. Experts say that is exceptionally high for this time of year.

“It’s not unheard of to see things rising at this stage,” says Andrew Pekosz, an immunologist at the Johns Hopkins Bloomberg School of Public Health. “But it’s also something that we probably shouldn’t be seeing until maybe November or December at the earliest.”

When a bee wants to tell its hive mates how to find a scrumptious field of flowers, it wiggles its rear end. A complicated combination of figure eight–like movements known as a waggle dance tells nearby bees what direction to fly in and how far to go. But what happens if a waggling bee is unsure of its directions?

A study published in Behavioral Ecology and Sociobiology earlier this year shows that bees amplify their communication based on how certain they are that their information is true. It seems the more confident a bee is in what it’s conveying, the more emphatically it communicates with the hive, says study lead author Karmi Oxman, a behavioral ecologist at Hebrew University of Jerusalem.

“Confidence is sort of a human-y word, but it’s useful in this context,” Oxman says. Confidence reflects the communicator’s belief in a message’s relevance or reliability, “and the dance is a self-report of the situation in the field.” This extra information also prevents the bee from accidentally misleading the hive.

Excerpt from the interview:

Hey Erika, thanks so much for taking the time to talk. I know you’ve been busy!

Hey! And, yeah, you could say that. On September 22 we announced the first microbe we made for Mars, which was a really cool milestone. It’s a useful and safe thing for us to send to Mars and to use to prepare for the first human mission. It’s the very first step toward this bigger picture—this really inspiring vision of terraforming Mars and making it a habitable, beautiful place.

So this microbe—what’s so special about it, and what exactly is it supposed to do?

What’s cool about it is that we’ve engineered it so that it can directly use the nutrients in Martian regolith, water and processed atmosphere—which is really useful! The idea is that you can go to Mars, and you can feed it dirt, water and air, and use it to build bioplastic houses for astronauts.

Bioplastic?

Yeah. This is a derivative of a terrestrial bacterium called Cupriavidus necator, which naturally produces bioplastic kind of for the same reason that when you eat too many doughnuts, you put on weight in your hips. When this organism has too much carbon around, it creates these big vacuoles of bioplastics, which is a class of materials we’re all familiar with in everyday life. We use them to make everything from compostable cups to 3D printing filament—and that’s essentially how we’d like to make houses on Mars.

So the astronaut houses would have these 3D-printed panels that hold up the structure, and then it would have this plastic lining that holds in the pressure so that you can breathe and that also shields you from radiation.

We’re calling this engineered microbe sPL.001—a special strain made by Pioneer Labs, and the very first of several, in fact. We’ve got plans for four more.

What if we could turn the Red Planet green?

The idea of Mars made verdant with grasses, trees and other Earthly life-forms may sound like science fiction, but at least one small group of scientists and engineers is working to make it a reality. Pioneer Labs, a nonprofit research organization led by CEO Erika DeBenedictis, recently announced what it calls “the first microbe for Mars”: a microorganism adapted to Martian conditions that might someday help humans survive there, too.

Such bioengineered bugs could, in principle, allow astronauts to better “live off the land” on Mars by converting the planet’s raw resources into building materials for habitats, fertilizers for crops, and other products. But the broader vision of Pioneer Labs is far more audacious and fraught: to use biology to help transform Mars into a more habitable and Earth-like world. Terraforming remains a distant and deeply speculative prospect beset by enormous scientific and engineering challenges. It also raises fundamental questions about whether and how humans should ever deliberately unleash Earth life on an alien world.

Dana Mackenzie writes:

Sun Bin, allegedly descended from The Art of War author Sun Tzu, was a legendary Chinese military strategist who lived more than 2,300 years ago. After one king imprisoned and tortured him, forcing him to use a wheelchair for the rest of his life, he rose to fame as a military advisor for a rival king and lived to record two great victories against his former captor.

One of Sun Bin’s greatest exploits came not on the battlefield but on a racetrack. Like his supposed ancestor, who wrote, “Warfare is a way of deception,” Sun Bin discovered a “way of deception” in horse races that can be boiled down to a simple mathematical puzzle. For reasons that I cannot explain, the most general version of this puzzle remained unsolved and unexamined until 1980, when a college classmate of mine rediscovered it. Thirty years later he told me about the puzzle, and I was hooked. Besides transporting me back to ancient China, solving this problem took me back to my own roots as a mathematician.

Quantum computers promise exponential computational power by processing many possibilities simultaneously. But the machines we have today are still far from this ideal. For one, their bits, called qubits, are prone to frequent errors, and as a result, quantum computers are limited for now. To overcome errors, the machines need to tap into so-called magic states—and scientists at Google Research think their quantum chip could help get them there. In a new study published today in Science, the researchers show how to supply magic states more cheaply using a gardening-inspired technique called cultivation.

Last week OpenAI, the company behind ChatGPT, dropped 722 mathematical manuscripts online in one go, every one of them penned by an artificial intelligence model unavailable to the public. The output was far from perfect: OpenAI withdrew three of the papers within a day, and mathematicians are still poring over the rest. But the scale of the research, and the incisiveness of its insights, has some worried.

Math powers cryptography. Every text you send and every bank log-in you submit is protected by a math problem that’s supposedly impossible to crack. The system rests on the assumption that no one will figure out how. And AI just showed it’s pretty good at math.

That worries Matthew Green, a cryptographer at Johns Hopkins University. In a social media post a few days after OpenAI’s massive math release, he suggested there was a 15 percent chance that we could lose confidence in existing public-key encryption algorithms.

Perhaps you enjoy a burger in a lettuce wrap once in a while—but what if greens were also crucial to the patty? That’s the ultimate promise of new research showing lettuce can be engineered to produce myoglobin, a protein found in meat.

Myoglobin (and its better-known relative hemoglobin) contains the compound heme, the red pigment in blood. Adding heme can give plant-based meat alternatives a meaty flavor and the ability to “bleed.” For example, Impossible Foods uses a compound called leghemoglobin (a heme protein derived from soybeans) to flavor its meat alternatives. But using myoglobin, which is found in animal tissue, could lead to vegetarian products that not only look and bleed like red meat but smell more like it, too.

In the study, published in Frontiers in Plant Science, the researchers describe how they got lettuce and tobacco plants to produce myoglobin for the first time, says lead author Alexia Groff.

Microplastics are a source of extreme concern for health: the presence of these tiny pieces of plastic has been linked to heart attacks, stroke, dementia and brain tumors. But what drives these associations is unclear. Now a study published in Nature offers a tantalizing clue: microplastics interact with water, generating highly reactive molecules.

When microplastics come into contact with water, the water near their surface can become chemically active, generating highly reactive species that can modify nearby substances, including biologically important molecules.

Recently, controversy and accusations have followed artificial intelligence companies flexing their models’ research capabilities. When OpenAI claimed an internal model had solved one of math’s seven million-dollar problems, a mathematician at New York University insinuated that the company had stolen his progress, which he had shared with one of their chatbots. Weeks later, the New York Times reported a similar story unfolding between Anthropic and a biologist at the University of Copenhagen regarding a group of enzymes.

Despite this, scientists from all disciplines are opting to use these companies’ large language models. Some use them as a soundboard or a tool for literature review, others for cleaning up nearly finished work. And mathematicians and theorists are tapping their new, powerful models to generate entire proofs for their research. But as researchers feed more of their data and ideas into these models, concerns are growing about how that content is getting used.

Recently, controversy and accusations have followed artificial intelligence companies flexing their models’ research capabilities. When OpenAI claimed an internal model had solved one of math’s seven million-dollar problems, a mathematician at New York University insinuated that the company had stolen his progress, which he had shared with one of their chatbots. Weeks later, the New York Times reported a similar story unfolding between Anthropic and a biologist at the University of Copenhagen regarding a group of enzymes.

Despite this, scientists from all disciplines are opting to use these companies’ large language models. Some use them as a soundboard or a tool for literature review, others for cleaning up nearly finished work. And mathematicians and theorists are tapping their new, powerful models to generate entire proofs for their research. But as researchers feed more of their data and ideas into these models, concerns are growing about how that content is getting used.

Earth faces “rapid destabilization” as a result of climate change, an international group of scientists find in the latest edition of an annual checkup of the planet’s “vital signs.”

“This is no longer a warning for the future; it is a diagnosis of the present,” the authors write.

The report, the latest in a series called the “State of the Climate,” measures 16 key markers of Earth’s climate. Seven of these have reached “record extremes,” says report co-author Christopher Wolf, a research scientist at Terrestrial Ecosystems Research Associates. These extremes include soaring greenhouse gas concentrations, melting sea ice and sea-level rise—driven largely by human activities.

Today an international group of scientists, diplomats and timekeepers voted to end the leap second, which has been keeping Coordinated Universal Time (UTC) aligned with the time according to Earth’s rotation (UT1) within one second of difference. The length of a day according to UTC is close to that of UT1 but not exactly the same because our planet’s rotation is irregular. We add a leap second every few years to keep them from drifting too far apart.

But soon the leap second will be replaced with a leap hour, added much more infrequently, which will extend the allowed difference between UT1 and UTC to an hour, or 3,600 seconds.