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Yep. There are lists of the molecules we've detected: https://en.wikipedia.org/wiki/List_of_interstellar_and_circumstellar_molecules, https://www.astrochymist.org/, https://arxiv.org/abs/2109.13848 (last is a regularly updated, curated, peer reviewed list maintained by Brett McGuire)

You mean to tell me y’all can see molecules in space?

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Astronomy, the field where Oxygen is a metal, and four orders of magnitude can be a rounding error. Love it.

Out of curiosity, why this divide? Is it just because hydrogen and helium constitute such large part of all matter that it makes no sense to divide the tiny remaining part further?

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I don't know, sorry. My strategy to learn about that would be to search NASA's ADS, though: https://ui.adsabs.harvard.edu/search/filter_database_fq_database=AND&filter_database_fq_database=database%3A%22astronomy%22&filter_property_fq_property=AND&filter_property_fq_property=property%3A%22refereed%22&fq=%7B!type%3Daqp%20v%3D%24fq_database%7D&fq=%7B!type%3Daqp%20v%3D%24fq_property%7D&fq_database=(database%3A%22astronomy%22)&fq_property=(property%3A%22refereed%22)&p_=0&q=martian%20salt&sort=date%20desc%2C%20bibcode%20desc (you don't need all those filters, but they help a bit)

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There's no matter present, but there's electrons, protons, and ions? These things are not matter?

What’s the salt content like on mars (if you know)?

Those herds of migrating quadrupeds evolved from land-based quadruped ancestors, like most mammals. They already had an effective mode of locomotion for their environment that could develop and become more refined.

Our most direct ancestors were tree dwellers, with hands for hands and hands for feet, with hands and feet that were both built for gripping branches, and shoulders and hips that were both built for climbing and swinging. So as our ancestor's environment became less tree-dense, we came from a very different starting point that animals that were already quadrupeds.

For whatever reason, it was more advantageous for our ancestors to develop bipedalism rather than returning to being quadrupeds. There are lots of factors here, and we don't know all of them. One very likely factor is that, we already had limbs adapted for grabbing stuff, and having two limbs free for holding and carrying things has proven to be extremely advantageous for us.

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Nothing is more humbling and numinous than the universe that stares us in the face

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It's ok to say it, but I think "same" might give the wrong sense, since it's not necessarily clear what "same" means here.

Correspondence is really the clearest concept - two retinal locations correspond in that they both respond to the same point in physical space, given certain optical & mechanical conditions. Those conditions are that the the physical point is at the same distance as the vergence distance of the two eyes (in other words, where they are both 'pointing', taking the axis of an eye to be a line between the center of the pupil and the foveola of the retina).

Under those conditions, a point in physical space will be imaged on precisely corresponding positions in the two retinas, and then I suppose it's fine to think of those as "the same positions".

You get the finest depth information, about the smallest differences in depth, from slightly different inputs both from the "same" i.e. precisely corresponding positions. The coarser the spatial grain (i.e. the more spread out in space it is), the larger the depth it can signal. So coarser depth signals will be transmitted by neurons with larger receptive fields, and potentially also by neurons with looser or less precise binocular correspondence. but I think the general rule will be that binocular neurons are for corresponding positions, and lack of precision amounts to noise, not a special source of information in itself.

The takeaway is not that the amounts available are nontrivial; rather, it's that we are trivial.

There is something so special about this kind of interaction that gives me hope for the internet.

Thanks for the insights.

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It was 15 years ago so I probably mis-remembered it. My chem professor did a lot of rotational spectroscopy and had invited someone from HEXOS to give a presentation.

I know the stuff I looked at at room temp looked like a bunch of noise. I tried writing some algorithms to help fix parameters of the molecule to match observed spectra and it went badly above something like 50 K. I'm surprised you were able to pick out transitions near a star! Nice work.

itz zpectral linez have alzo been found in variouz aztronomical objectz