Astronomy

Tiny fossils hint at when birds began making their mind-blowing journey to the Arctic to breed

More than 13.8 million Americans could have Alzheimer’s by 2060, and at the rate care facilities are closing, many of them will have nowhere to go. Regina Shih of the State Alzheimer’s Research Support Center (StARS) wants to help solve that problem

While our understanding of Alzheimer’s disease is far from complete, the latest therapies, and others in more than 100 clinical trials, offer new hope

Inertial confinement reactors, stellarators and tokamaks each have pros and cons

Breakthrough therapies, new diagnostics and preventive measures for fighting a devastating disease

As warming temperatures bring more extreme rain to the mountains, debris flows are on the rise

Writers, artists, photographers and researchers share the stories behind the stories

Science in meter and verse

Science may need to increasingly rely on wealthy patrons, but privately funded projects don’t always pan out

Black Americans face a significantly higher risk of Alzheimer’s and other dementias than white Americans. Researchers are working to find out why that is and how to intervene

An abandoned plan to visit another star highlights the perils of billionaire-funded science

New Alzheimer’s drugs known as anti-amyloid therapies may slow disease progression—but they also carry serious risks, including brain bleeds and strokelike symptoms

Charming quarks; the first Batman signal

Forest ecologist Mark Harmon has been exhaustively examining dead logs for 40 years, and he’s found a complex world few people see

Letters to the editors for the May 2025 issue of Scientific American

A new generation of Alzheimer’s blood tests could speed up diagnosis and access to care—but they also raise thorny questions about prediction, treatment and uncertainty

Pets can improve your health—but only if you have a strong relationship with the animals

Which of these knots are secretly “unknots”? Try our math puzzle to find out

Play this crossword inspired by the October 2025 issue of Scientific American

Early studies suggest that lifestyle changes such as diet, exercise and social engagement may help slow or prevent Alzheimer’s symptoms—but the evidence is inconsistent, and many doctors remain cautious