Learning things...twice.

Have you ever learned something twice?

Have you ever learned something, forgot it, and learn about it later only to realize you already knew that?

Sometimes, it can be kind of embarrassing. Especially if you tell something you are convinced is true only to find out you knew better. That happened to me today.

At The Curious Wavefunction, Ashutosh posted about an article in the New York Times about radio signals and early stars. He identified a rather curious statement in the article:

Dust grows over time as stars manufacture heavy elements called metals, like carbon, silicon and oxygen, that make up dust and then spit them out into space.

I checked out the article and found the offending sentence and it offended my delicate chemistry teacher sensibilities. Carbon, silicon and oxygen are most decidedly NOT metals, nor are they "heavy elements."

I decided I had finally found my purpose on this planet and decided to send the author an email and personally advance his education. This is what I sent him:

Mr. Overbye,
In a recent article you wrote: "Dust grows over time as stars manufacture heavy elements called metals, like carbon, silicon and oxygen, that make up dust and then spit them out into space." Carbon, silicon and oxygen are most certainly NOT metals nor are they heavy elements.
Best wishes,
Eric Woller, Ph.D.

I added the Ph.D. part to make sure he knew I wasn't messing around. I felt good. I had taught some big shot NYT science correspondent some damn fine chemistry. He was nice enough to reply. This is what he sent me:

Astronomers refer to anything heavier than helium as metals.
Thanks for writing,
Dennis

That was when I slapped my forehead and realized...I knew that. I'm such an idiot.

While one can argue that labeling anything heavier than helium as a metal is silly, that's what astronomers and the like do. I knew that, but it didn't stop me from displaying some degree of ignorance.

So, I learned that little fact...again.