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Comment by ffffwe3rq352y3 | Hacker News Reader

Very interesting! I don't know much about this and the article did not go into detail: What does "organics" mean specifically?

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Good question.

In astrobiology (and I think also in biology and most of chemistry) it means any molecules that contain carbon, with a few exceptions (exceptions include carbon dioxide and diamond - they don't count as organic). Strange definition, perhaps, but I'm certain that's what it means in astrobiology.

Organic molecules are not necessarily in living things and, indeed, interstellar dust clouds contain huge quantities of amino acids and other organic molecules which most astronomers believe have never been near a living thing.

There's no terribly good definition of organic molecules in chemistry. The traditional definition is something that required a living organism to produce it, until inorganic synthesis of organic urea ruined that idea. The typical rule of thumb is an organic compound contains C-C and C-H bonds, but there's a whole host of exceptions to that rule (including urea, which lacks both C-C and C-H bonds).

The best I can come up with is that organic chemistry is the study of the interactions of a set of common structural motifs (called functional groups), and an organic molecule is something that contains those functional groups.

Be grateful these astronomers even made that distinction. They might have just said this stuff (or at least the parts of it that aren’t Hydrogen) was ‘metallic’ and left it at that.

https://en.wikipedia.org/wiki/Metallicity

Seems like asteroid astrophysicists like to be a bit more specific about this stuff than their stellar and galactic astrophysicist colleagues.

being technically right is good, but if you want funding, it has to be way more sexy sounding than that.

Yes!

Happily, it's become okay for them to talk about astrobiology. It was mostly taboo until a few years ago. (Just speculating here, but I think it was the discovery of lots of exoplanets that caused astrobiology to become permissible.)

Correct, this is the definition throughout all of biology, chemistry, and physics. Merely molecules with carbon atoms.

Unspecified in this article, but organics we've found in meteorites (fallen asteroids and comets, mostly) include the same carbohydrates, fatty acids, nucleic acids, and amino acids that all known life is built from.

In the broadest sense, organics could refer to any molecule of carbon and hydrogen, however I don't think that's how it's used here.

To me it basically means carbon-based

Edit: didn't see any academic paper linked in the article (assume they're still working on it all) but the following is mentioned

> In a preliminary analysis of some of the dust, Lauretta said scientists hit the jackpot with a sample that is nearly 5 percent carbon by mass and has abundant water in the form of hydrated clay minerals.

Organic compounds. Generally, containing carbon and carbon-hydrogen bonds.

I'd also go with this one.

> Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.

https://en.wikipedia.org/wiki/Organic_chemistry

> In chemistry, many authors consider an organic compound to be any chemical compound that contains carbon-hydrogen or carbon-carbon bonds, however, some authors consider an organic compound to be any chemical compound that contains carbon.

https://en.wikipedia.org/wiki/Organic_compound

As best as I can tell, it means that the sample is 5% carbon, with no indication of whether that carbon is contained in glucose or in carbonate.

Organics would be compounds containing carbon.

Hydrocarbons and it's derivatives not specifically carbon containing compound.

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