New observations from the James Webb Space Telescope hint that the universe’s first stars might not have been ordinary fusion-powered suns, but enormous “supermassive dark stars” powered by dark matter annihilation. These colossal, luminous hydrogen-and-helium spheres may explain both the existence of unexpectedly bright early galaxies and the origin of the first supermassive black holes.

In the early universe, a few hundred million years after the Big Bang, the first stars emerged from vast, untouched clouds of hydrogen and helium. Recent observations from the James Webb Space Telescope (JWST) suggest that some of these early stars may have been unlike the familiar (nuclear fusion-powered) stars that astronomers have studied for centuries...

In a new study using AI and machine learning, EPFL researchers have found that it’s not only what we eat, but how consistently we eat it that plays a crucial role in gut health.

The gut microbiota is the community of microorganisms, including bacteria, viruses, fungi and other microbes, that lives in our digestive systems—some of these microbes are helpful and others can be harmful.

Many previous studies have shown that what we eat has an impact on our gut microbiota...

Using 11 years of magnetic field measurements from the European Space Agency’s Swarm satellite constellation, scientists have discovered that the weak region in Earth’s magnetic field over the South Atlantic—known as the South Atlantic Anomaly—has expanded by an area nearly half the size of continental Europe since 2014.

Earth’s magnetic field is vital to life on our planet. It is a complex and dynamic force that protects us from cosmic radiation and charged particles from the sun.

It is largely generated by a global ocean of molten, swirling liquid iron that makes up the outer core around 3000 km beneath our feet...

Scientists at Washington University School of Medicine in St. Louis have uncovered a new way that brown fat, a type of fat that burns energy, can boost the body’s metabolism. This process allows cells to consume more fuel and generate heat, improving overall metabolic health. Conducted in mice, the research points to new possibilities for using brown fat to address metabolic conditions such as insulin resistance and obesity.

The findings were published Sept. 17 in Nature.

Brown fat is unique because it turns energy (calories) from food into heat. Unlike white fat, which stores energy, or muscle, which uses it immediately, brown fat helps keep the body warm in cold environments...