MICHAEL (WOULD NOT TOUCH PLUTO WITH A TEN FOOT POLE) SHARA: Oh, I have some huge problems. I think it's a terrible proposal as it stands.

Actually, a strict reading of the current rules means that Saturn is no longer planet because Saturn isn't a perfect sphere. Saturn is about 10 percent off-round because it's spinning so fast. But that's a minor point.

ALAN (MO PLANETS MO LOVE) STERN: {...}By the way, what Dr. Shara just told you is incorrect. In fact, the definition doesn't have to do with whether an object is round; it's whether it's large enough for gravity to dominate over its material strength to make it flow into a sphere. So Saturn certainly qualifies. I think he should read it a little closer.

JEFFREY BROWN: Well, Dr. Shara, come back. Go ahead.

MICHAEL (YOU SUCK, BUT THAT'S A MINOR POINT) SHARA: The spherical symmetry is specifically called out, as is hydrostatic equilibrium. And then the question becomes, well, how round does an object have to be in order to be considered a planet? But that's a minor point.

The real weakness of all of this is that there is no fundamental physics. An object will either be round or not or in hydrostatic equilibrium or not to some extent, depending on what it's made up of, how quickly it's spinning, how massive it, not how it got to be what it is.

We ignore in the current set of definitions the evolution of the Solar System. And the idea of accretion, the idea of an object that dominates all the others within its own gravitational range, is really the basic idea behind the way the Solar System formed, the way the planets formed. And that is, I think, a far better way of defining what a planet is.