Jupiter Not the Planetary Protector We Thought it Was?

I've always liked the idea that Jupiter has acted like a protector to its little brother, Earth. That it has used its massive gravitational pull to divert asteroids and comets from a collision course with Earth. Maybe Jupiter even felt bad when one got through, and doomed the dinosaurs to extinction. But a new study has cast this idea into doubt. The idea of Jupiter as a protector has been around for a while. The images of comet Shoemaker-Levy 9 breaking apart and crashing into Jupiter in 1994 r...