The universe is expanding, and that expansion is accelerating. But what is causing that to happen? The leading hypothesis is a repellent force that astrophysicists refer to as “dark energy,” which ...

Kangaroos can hop faster without using more energy. A new study explains how posture and tendons make this possible.

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. The best armor, if it could be devised, would weigh absolutely ...