Letter from the Southwest The Decline of Outside Magazine Is Also the End of a Vision of the Mountain West After its purchase by a tech entrepreneur, the publication is now a shadow of itself.

The sun rises and sets every day. We plan our lives around it. It's ironic, then, that "we know so little about the star at the center of our solar system," says Matina Gkioulidou, a space physicist ...

Haile can make both on demand. Although the sun’s energy is inarguably an enormous resource, researchers have long experienced difficulty harnessing it. Solar cells, which have advanced significantly ...

The Earth-orbiting Solar Dynamics Observatory takes spectacular portraits of the sun, like this ultraviolet view of active regions captured in 2015. In July, humanity will dispatch its first ...