Astronomers analyzing gravitational-wave data from the LIGO-Virgo-KAGRA Collaboration have reported that merging binary black holes fall into three distinct categories. The study shows that the three subpopulations have their own characteristic masses, spin behavior, and merger rate that may be linked to different dominant formation mechanisms. The paper outlining their results was submitted to the preprint server arXiv on March 18.

A mix of three
The data in the fourth gravitational-wave catalog (GWTC-4), released by the LIGO-Virgo-KAGRA collaboration, included more than 150 detected black hole mergers...

Health organizations are starting to raise concerns about the potential long-term impacts of artificial sweeteners, which taste sweet but—unlike sugar—contain no calories, suggesting they could interfere with energy metabolism and increase the eventual risk of diabetes or cardiovascular disease.

Now a new study in mice indicates that the popular sweeteners sucralose and stevia have negative effects on the gut microbiome and gene expression, potentially compromising metabolic health, which can be transmitted between generations.

“We found it intriguing that despite the growing consumption of these additives, the prevalence of obesity and metabolic disorders such as insulin resistance has not declined,” said Dr...

Researchers have developed a simple and ecofriendly way to use a laser to turn natural leather into flexible and wearable energy devices. The new approach could lay the groundwork for more sustainable wearable electronics. In a paper in Optics Letters, the researchers demonstrate the new technique by creating microsupercapacitors on leather in various patterns, including a tiger, dragon and rabbit.

“Using a laser, we directly write conductive patterns onto vegetable-tanned leather to create microsupercapacitors that can store energy and help smooth electrical signals so that wearable e...

Earth may be habitable because it got unbelievably lucky with its chemistry from the very start.

Earth may have won a cosmic chemistry lottery. Researchers found that during the planet’s earliest formation, oxygen had to be in an extremely narrow “Goldilocks zone” for two life-essential elements, phosphorus and nitrogen, to stay where life could use them. Too much or too little oxygen, and those ingredients could be lost or trapped deep inside the planet. This could reshape the search for life by showing that water alone is not enough.

Life cannot begin on a planet unless certain chemical elements are available in large enough amounts. Two of the most important are phosphorus and nitrogen...