When it comes to escaping predators, the day octopus is all about working smarter, not harder. 🐙

For more than a century, students around the world have been told that pressure and friction make ice melt. The familiar winter slip on a frozen sidewalk is often blamed on body weight pressing through the sole of your (still warm) shoe. New research from Saarland University indicates this view is incomplete, finding that slipperiness stems from interactions between molecular dipoles in the ice and those in the contacting surface, such as a shoe sole, rather than from pressure or friction.

The study by Professor Müser and colleagues Achraf Atila and Sergey Sukhomlinov challenges a model put forward nearly two hundred years ago by the brother of Lord Kelvin, James Thompson, who suggested that pressure and friction, along with temperature, cause ice to melt.

“It turns out that neither pressure nor friction plays a particularly significant part in forming the thin liquid layer on ice,” explains Martin Müser. Instead, computer simulations by the team reveal that molecular dipoles are the key drivers behind the formation of this slippery layer, which so often causes us to lose our footing in winter.

But what exactly is a dipole?

PET plastic is one of the most widely used types of plastic in the world, but when it has served its purpose, it becomes a pressing global environmental issue. This is because it ends up in landfills in many parts of the world, where it breaks down into polluting microplastics that spread to the air, soil and groundwater. A large portion also end up in the oceans.

With the new chemical technology, researchers can transform PET plastic waste that is overlooked by recyclers into a primary resource in a new form of CO2 sorbent they have developed. The process "upcycles" it to a new material the researchers have named BAETA, which can absorb CO2 out of the atmosphere so efficiently that it easily compares with existing carbon capture technologies.

The trial results, published Thursday (Sept. 4) in JAMA, include data from 194 people with moderate to severe anxiety across the U.S. The study compared these participants' responses to different doses of LSD against a placebo treatment. It found that the drug alleviated symptoms in many patients for at least three months after just one exposure.

That said, participants who were given low doses of LSD — either 25 or 50 micrograms — did not see a significant change in their symptoms. The effect kicked in only at higher doses — either 100 or 200 micrograms — and those given 100-microgram doses had the best results.

In fact, 12 weeks out from treatment, about 47% of the people who were given 100 micrograms were in remission, based on a standardized anxiety rating scale. And about 65% of the people in that group saw their scores on the scale fall by at least half. By comparison, only about 20% of the placebo group was in remission at the 12-week mark and about 30% saw their scores halved.

Deep in Earth's past, an icy landscape became a seascape as the ice melted and the oceans rose off what is now the northeastern United States. Nearly 50 years ago, a U.S. government ship searching for minerals and hydrocarbons in the area drilled into the seafloor to see what it could find.

It found, of all things, drops to drink under the briny deeps—fresh water.

This summer, a first-of-its-kind global research expedition followed up on that surprise. Drilling for fresh water under the salt water off Cape Cod, Expedition 501 extracted thousands of samples from what is now thought to be a massive, hidden aquifer stretching from New Jersey as far north as Maine.

It's just one of many depositories of "secret fresh water" known to exist in shallow salt waters around the world that might some day be tapped to slake the planet's intensifying thirst, said Brandon Dugan, the expedition's co-chief scientist.

A commonly prescribed antidepressant may also strengthen the body’s defenses against cancer, according to new research from UCLA.

The study, published in Cell, showed that selective serotonin reuptake inhibitors (SSRIs) improved the cancer-fighting ability of T cells and reduced tumor growth in several types of cancers across both mouse and human tumor models.

“It turns out SSRIs don’t just make our brains happier; they also make our T cells happier — even while they’re fighting tumors,” said Dr. Lili Yang, senior author of the new study and a member of the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA. “These drugs have been widely and safely used to treat depression for decades, so repurposing them for cancer would be a lot easier than developing an entirely new therapy.”

Our boldest photography project yet!

From Above & Below, a mission to photograph the same subjects from Earth and space with National Geographic photographer, Babak Tafreshi.

BabakTafreshi traveled the world while I orbited around it, and together we created this perspective.

Lucky shot during the eclipse