Tag Archives: solar systems

TWSB: Planetary Perturbers: Space’s Version of Peer Pressure

So this is pretty awesome: apparently NASA’s found a Jupiter-sized planet that orbits its sun in the opposite direction of the sun’s rotation. No, this isn’t like Venus rotating in the opposite direction of the other planets…this is a planet revolving its sun in a direction that supposedly defies physics.

Wait, how in the hell…?

Let’s start with how solar systems are formed. First you need a huge cloud of particles. The collapse of this cloud and the result of the pull of gravity causes the cloud to begin to spin. As it spins, the densest part of the cloud condenses and forms a sun.  Less dense parts condense into smaller balls of matter and become planets.

Now it makes sense, since all these stars and planets and such arose from a single spinning cloud of debris, that the balls of matter would all be either rotating (the sun) or orbiting (the planets) in the same direction, the direction of the original spinning cloud.

So how the heck could a planet single itself out and rotate in the opposite direction?

NASA scientists suspect that the change in rotational direction is actually due to the influence of a planet external to the solar system containing the rebel revolver. They suspect that the opposite-orbiting planet originally revolved around the sun in the correct direction. However, it was also close to another planet, most likely a giant, that was slightly further away from the sun. Thus, it was stuck in a sort of gravitational tug-of-war. Its gravitation interacted with the giant planet’s gravity, with each pass between the giant planet and the sun causing a decrease in the angular momentum  in the planet in question.

As the planet began to lose its momentum, it began spiraling in towards its sun (since momentum is what keeps planets from just falling into their suns). But because its plunge to near certain doom gives the planet some additional angular momentum in the opposite direction of the sun’s rotation. This additional momentum causes the planet to stabilize  and establish a new orbit—one in the opposite direction of the rest of the solar system.

And how freaking crazy is that?