It's true: Stress does turn hair gray (and it's reversible)

Some seafloor microbes can take the heat: And here's what they eat

Antelope's fate shrouded by social, political forces

The most extreme space weather occurs when the Sun blasts billions of tons of energized particles toward Earth at speeds up to 6.7 million mph (3,000 km/s). Known as coronal mass ejections, these explosions can cause intense geomagnetic storms, as well as negatively affect astronauts and spacecraft.