Sexuality and gender play a profound role in shaping identity, but for much of human history how they are determined has remained obscure. How does sexual orientation develop? What is it? Can it be changed?

Einstein dreamed of a unified theory of nature’s laws. String theory has long promised to deliver it: a mathematically elegant description that some have called a “theory of everything.” Join …

A second doesn’t always feel like a second—time can seem to slow down if you’re riding a death-defying roller coaster, or speed up while you’re having a night out on the town. But just what’s going on inside our heads to skew our perception of time?

The first electron microscopes enabled scientists to finally view the nanoworld. But because of limitations in the microscope’s lenses, achieving sharp images of individual atoms was not possible. For 60 …

Stuntman and special effects coordinator Steve Wolf shows how actors can fall from a 20-story building without injury and how houses can be set ablaze safely in movies…all through science. …

In his research, U.K. Astronomer Royal Martin Rees has tackled topics as varied as the Big Bang, quasars, and more far-out ideas like the search for dark matter and the …