Messages from Mercury
After orbiting the solar system’s smallest, innermost planet for just six months, NASA’s MESSENGER spacecraft is relaying some intriguing observations. For one, MESSENGER team members reported October 5, Mercury’s magnetic field is offset from the planet’s core: it’s centered 480 kilometers to the north of center, a distance roughly 20 percent that of the planet’s diameter. Atmospheric calcium curiously clusters near the planet’s equator at dawn. And a 99 percent complete surface map reveals a complex area of former volcanic activity in the northern hemisphere. It’s also possible for ice to exist on this smoldering world: as is true for Earth’s moon, there are perpetually shadowed hollows in Mercury’s surface. At the poles, these areas are tucked into craters — super-shady places that make perfect hidey-holes for ice. — Nadia Drake
Note: To comment, Science News subscribing members must now establish a separate login relationship with Disqus. Click the Disqus icon below, enter your e-mail and click “forgot password” to reset your password. You may also log into Disqus using Facebook, Twitter or Google.