On Earth, most of us rarely have to think about the signals that keep our internal clocks aligned. The sun rises, daylight changes, darkness arrives and morning comes again.

Our bodies have evolved alongside this roughly 24-hour cycle. Light is one of the strongest signals our bodies use to synchronize the circadian clock. But what happens when the sun no longer provides a reliable schedule?

A spacecraft orbits Earth roughly every 90 minutes, so astronauts experience about 16 sunrises and sunsets every 24 hours. They cannot go to sleep every time the sun disappears—but their bodies still need to know when it is time to sleep, wake, eat, exercise and work.

This makes spaceflight more than just an engineering cha...

Omega fatty acids have long been recognized for their benefits: supporting cardiovascular health, reducing systemic inflammation, and promoting brain development and cognitive function. But scientists now warn of a long-unrecognized downside to these compounds when it comes to cancer and immunotherapy.

New preclinical experiments by medical investigators in the Vascular Biology and Therapeutic Program at Yale University School of Medicine show that omega fatty acids can blunt the cancer-killing capabilities of the immune system’s natural killer cells.

Their research is part of a growing body of evidence suggesting that well-known—and largely beneficial—fatty acids can circumvent the body’s defenses and promote cancer growth.

A unifying he...

Magnetic fields in the chromosphere above a quiet-Sun region observed by the SCIP instrument onboard Sunrise-III (right box), and magnetic structures reproduced by a numerical simulation (left box). The thin, thread-like magnetic structures detected by SCIP are reproduced in the simulation as twisted magnetic field lines (enlarged view inside the circle at the lower left). （Credit: NAOJ / MPS / Sunrise-III/SCIP）

A team of researchers led by the National Astronomical Observatory of Japan discovered unexpectedly intricate magnetic structures above quiet-sun regions by observing the sun with the balloon-borne solar observatory Sunrise-III during its 2024 flight in Earth’s stratosphere. The work is published in The Astrophysical Journal Letters.

Threads within the magnetic canop...

When scientists assess how dangerous a bacterium is, the first question often seems simple: Can it be stopped or killed? In microbiology and antibiotic research, one of the classic readouts has been whether a bacterium can grow in the presence of a given treatment. The bacterium either grows or it does not. The drug either stops it or it does not.

But infection is not just a survival contest...