this post was submitted on 12 Jul 2023
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Astronomy

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Note: Organic matter does not mean life. It is a precursor to life. It does make the possibility of life on ancient Mars more likely.

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[–] [email protected] 9 points 1 year ago (1 children)

Itll be interesting to see the results once the samples are brought back next decade. I hope we can make mars a "national park" so we don't screw with it too much.

[–] [email protected] 4 points 1 year ago (1 children)

I hope we can make mars a “national park” so we don’t screw with it too much.

Unfortunately, I think it's much more likely that we will exploit it for any resources we can.

[–] [email protected] 1 points 1 year ago

😩 even just watching the rover dump samples on mars surface fills me with frustration. Where humanity goes, there shall be rubbish

[–] [email protected] 7 points 1 year ago (1 children)

Chemists: If it contains carbon it's organic

Anyway, here's the Nature paper:
https://doi.org/10.1038/s41586-023-06143-z

And here's the table listing the actual organic molecules detected:
https://www.nature.com/articles/s41586-023-06143-z/tables/3
Including benzene and naphthalene, and amine acids lysine, tyrosine, phenylalanine, histidine, etc.

Curiously, only L-amino acids were detected. Did they test for D-aa and didn't see any, or did they test for L-aa only? The paper doesn't say. If the former, that's a pretty big deal. As far as I know there is no inorganic process that can produce non-racemic chiral molecules.

[–] [email protected] 3 points 1 year ago

Ah! This reference paper goes into more detail about how the reference spectra for the Raman fluorescence were acquired: https://doi.org/10.1089/ast.2022.0023 They built a fluorescence spectrometer identical to the SHERLOC tool onboard the Perseverance rover on Mars and tested it against a library of molecules of interest, including all L-amino acids and a few of the D-amino acids. Turns out the spectrometer cannot differentiate between the two:

The fluorescence spectra of d-phenylalanine and l-phenylalanine were almost identical, showing no obvious dependence on the chirality of the α-carbon.

Raman fluorescence spectra of 20 amino acids