The Biggest Beltway: "Astronomers have discovered a newly forming solar system with the inner part orbiting in one direction and the outer part orbiting the other way." Why is this significant?

Our solar system is a one-way boulevard. All the planets -- from Mercury out to Pluto and even the newly discovered objects beyond -- revolve around the Sun in the same direction. This is because the Sun and planets formed from the same massive, rotating cloud of dust and gas. The motion of that cloud set the motion of the planets.

The fact that a solar system can have planets running in opposite directions is a shocker.

"This is the first time anyone has seen anything like this, and it means that the process of forming planets from such disks is more complex than we previously expected," said Anthony Remijan of the National Radio Astronomy Observatory.