Science: Us Figuring Out the World

Hello random Internet user,

Chances are you are here because you read Natasha Hurley-Walker's excellent article "What is Space Made of? It's Complicated..."  It's really good, and not just because of my very simple explanation of the Periodic Table of the Elements for Astronomers.  (And here I was thinking you were here for my books.)

Anyhoo, astronomers really do classify the elements of the universe as Hydrogen, Helium and metals.  Everything that isn't H or He is called a 'metal'.  For those into etymology, this is rather ironic, as the word metal comes from the ancient Greek word métallon, which means mine or quarry, suggesting that metals were something that were found, not made, like wood or wool or fire. In Astronomy, H and He are 'found', whereas metals were made by stars, in one way or another.

Various elements do have certain significance to astronomers for one reason or another.

The  CNO Cycle  is a fun one, and the Lithium Problem is another. The first goes to show us how much we know about the Universe, while the second shows us how little we know.

Probably our most interesting use of the metals in astronomy is through the observation of spectral lines.  Astronomy is almost purely an observational science, with very, very little hands-on experience. Pretty much everything we know about the universe has come because the information came to us, usually in the form of variances in the EM spectrum. As energy moves through the universe, the universe acts upon it, either by bending it, dilating it, or absorbing/re-emitting it.

Matter in the universe tends to absorb or emit at certain frequencies. If we find spectral lines that we know match up with certain elements, then we know that element is present.

Each and every elements does have a particular significance, and we're quite grateful for that mere 1-2% of non-hydrogen and non-helium in existence, which allows us to learn so much about our universe.

But yeah, ask an astronomer about the periodic table of the elements, and they're all, Hydrogen, Helium, and.... everything else.

The spectrum of the Sun, showing absorption lines, demonstrating its metallicity.
The Sun is a Population I star, meaning it's rather metallic, aka, it's full of dirt.

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More into astronomy and not so much into Romance novels? I have posted astronomy posts, including an A to Z series about Astronomy.  Go ahead and read those.  Otherwise, go read my novels. I've got three more out in October.