If Neptune's orbit shifts by 0.1 percent, the solar system could become unstable.

A passing star, or stellar flyby, with the capacity to shift Neptune's  

orbit by only 0.1 percent might spell disaster for the entire solar system.

But don't worry, according to a recent study, it won't happen in our lifetime.

Researchers at the University of Toronto used simulations to 

determine how close a passing star would have to be in order to  

alter a planet's orbit and start a chain reaction of changes, as well  

as the likelihood of that happening. "Just as the sun's gravity may

influence incredibly far things like comets, so comets can be very far away from the sun,