Topic: Comets in the news. Stealth Comets. A broken comet.

[Nemesis]

Stealth Comets

Three comets exhibiting quite uncomet-like behavior have been found orbiting the Sun in a manner more expected of rocky asteroids. Dubbed “main-belt comets” by researchers, the objects suggests that comets and asteroids share more in common than previously thought, and that water found on Earth may have also taken root in the asteroid belt.

Broken comet

"This is a rare opportunity to watch a comet in its death throes—from very close range," says Don Yeomans, head of NASA's Near Earth Object Program at JPL.

There's no danger of a collision. "Goodness, no," says Yeomans. "The closest fragment will be about six million miles away--or twenty-five times farther than the Moon." That's close without actually being scary.