Astronomy

New research shows how the 'dancing' behaviour of dwarf satellite galaxies can predict mergers between their hosts. A distant pair of galaxies is undergoing the same type of merger that Milky Way/Andromeda will undergo. Can the behaviour of their dwarf satellites tell astronomers what will happen when the MW and Andromeda merge?

A stunning new image of a cosmic jet has helped astronomers unlock the mystery behind the unusually bright emission of high-energy gamma rays and neutrinos from a peculiar celestial object. The source is a blazar—a type of active galaxy powered by a supermassive black hole devouring matter at the heart of a galaxy. They have captured what looks like the mythical "Eye of Sauron" in the distant universe and may have just solved a decade-long cosmic puzzle.

Total reversals in scientific thinking are rare—but earth-shattering

Our anniversary celebration begins with an outstanding collection of stories about times that science itself has made a full about-face

More familiar smells and scents from complex molecules can often be more appealing

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

Other species exhibit capabilities that were once thought to be exclusive to Homo sapiens

The Juno spacecraft has rewritten the story on Jupiter, the solar system’s undisputed heavyweight

Synthetic polymers were supposed to free us from the limitations of our natural resources. Instead they led to an environmental crisis

Huge fish; spiritualist rebuke

Remarkable new treatments can free millions of kids and adults from the deadly threat of peanut allergy, tackling one of our fastest-growing medical problems

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

The search for extraterrestrial life has periodically been turned upside down

Science in meter and verse

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

Figure out how to split the square in this math puzzle

The U.S. is a global powerhouse. Public education is one of the main reasons why

Unless you have celiac disease, there are few health benefits to a gluten-free diet

Washing waste from the brain is an essential function of sleep—and it could help ward off dementia

Long dismissed as impossible, nerve regrowth is offering new hope for healing injuries and treating neurodegeneration