Oh wow. As of Oct. 21, 2015 they finally admit a few facts that I've been trying to solve with stellar metamorphosis.
However, the physics of planetesimal formation are not understood, or how the planets came to have their present chemical compositions. In particular, it is still not clear how these objects grow to become 0.1–1 km sized planetesimals; this problem is known as the "meter size barrier".
Okay, so it is a shock really. To outright say, "the physics of planetesimal formation are not understood" is pretty cool. It is not, "the physics of planetesimal formation are mostly understood", or, "the physics of planetesimal formation are not well understood"...
Seems like some stronger opinions are starting to win out. I think what's happening is that people are waking up to the reality that "the physics of planetesimal formation is based on wishful thinking". When you have physicists (astrophysicists in particular) being told for many years that nature clumps rocks and minerals together absent heat and pressure in the vacuum, without consulting their more down to Earth contemporaries, the geologists, then you have somewhat of a problem.
Further it is mentioned (newly albeit by some random expert I suppose on wikipedia) that it is not understood, "how the planets came to have their present chemical compositions". Well I'll be damned. This is a first for me. They actually note for the first time in astrophysics pages on wikipedia they do not understand how planets' chemical compositions came to be. Well ladies and gentlemen, when you have trillions upon trillions of tons of chemical compounds and molecules comprising the entirety of the planet, you better figure out somehow, some mechanism, SOMETHING, that could have formed all those chemicals in their vast quantities.
I'll give yall a hint: It has to do with stellar evolution itself, and the freely charged radicals which combine together releasing heat over many billions of years... It has to do with the fact that astronomers have stumbled their way into a deep abyss of educational nonsense, when the facts are right below their feet. There was no need to dig a pit, unless their true intentions were to bury their heads in it.
There is no meter size barrier. The barrier is about a few centimeters, it is the thickness of the astrophysicists' skulls themselves. Closed mindedness is the issue.