@tomnarock1 adding "& Planetary" seems completely reasonable to me.

Astrobiologist (part-time) here. Some (most) of our astrobiological work involves looking at terrestrial analogues for Mars and determining whether/how life could be observed there. It frequently involves a lot of geology. Exoplanets is more open -- but I think a lot of the exoplanetary modelling papers, especially for hot Jupiter big gassy planets already goes to arxiv and will continue to self-select to there.

I do not agree with the addition of planetary sciences to EarthArxiv, This would rather generalize the server. If that is the case, then we might well have to consider other areas of research for addition in future. The point is it would reduce the significance of the server title 'EarthArxiv', and unless we are willing to change the title, we should abstain from this addition.

It is true that planetary science is broad and it includes a very wide range of topics and disciplines (atmospheric, plasma, magnetospheric physics, etc.) . But papers dealing with "planetary geology", or - perhaps better - "planetary geoscience" would fit very well. Planetary geology papers sitting on ArXiv would be in fact better placed on EarthArXiv, instead...

There was a plaint a couple of days ago on Twitter (sorry, didn't keep the link) of a Planetary Scientist somewhat teed-off at always being a bridesmaid at meetings, but never getting the attention they consider their work deserves. AGU - subject distributed over multiple sessions ; Geochemists (I think - that's how I parsed the acronym) there are relevant topics, but it's splashed around over several subdivisions.
I can understand where they're coming from.
How much of an issue would it be to support such a section? And as a subsidiary, how to frame the logical boundaries for a paper to be considered relevant to both "Earth Science" and "Planetary Science"?

@aidankarley, there's not much involved in supporting "Planetary Science". The Advisory Committee decided to pursue supporting it based on the results of the poll. The only issue in doing so is framing the boundaries. To keep things consistent, we are proposing that the sub-terms of "Planetary Science" exactly match the existing sub-terms of "Earth Science", which are
Biogeochemistry,
Cosmochemistry,
Geochemistry,
Geology,
Geomorphology,
Geophysics and Seismology,
Glaciology,
Hydrology,
Mineral Physics,
Paleobiology,
Paleontology,
Sedimentology,
Soil Science,
Stratigraphy,
Tectonics and Structure,
Volcanology.
We also have in place a quick and informal manual review of all preprint submissions. Any preprints submitted outside of this scope, e.g. planetary astrophysics, would be rejected. That's the current plan we'd like to pursue with the Center for Open Science, which hosts EarthArXiv.

@All, apologies for the late reply.

From the public poll (the one I posted: https://www.loomio.org/p/e9ZV7cRq/add-planetary-science-to-the-taxonomy) it was clear that nearly everyone is in favor of adding Planetary Science, however, the poll specifically stated changing "Earth Science" to "Earth and Planetary Science" at the top level (well, top level of our domain).

I had a chat with @mattspitzer before the holiday break about this. We can request this edit, but this will not be backward compatible with any paper currently residing on the system, and it will cause some mismatch issues when searching across all *Xiv preprint servers on the main search page.

I, personally, think this is still the best option. However, as I don't really want to be the cause of a plethora of headaches for COS, my thinking is simply adding "Planetary Science" as a sub-term of "Earth Science". To me, this keeps with the spirit of the domain. I.e. a paper on Martian Tectonics is appropriate for EarthArXiv as it is applying Earth Science concepts to a planetary body. It's still a hack, but it makes more sense to me than having "Geology", "Geochemistry", etc. under "Planetary Science" as well as "Earth Science".

Futher, perhaps grouping terms like Geomorphology, Geophysics, etc. under (as sub-terms) Geology provides additional clarity.

@tomnarock1 are you able to share further insight into the splitting option you have described?

Would it be possible to keep on using the old taxonomy, but add tags for “Planetary Science” or “Earth Science”?

Having tags may anyway be nice, the current categories are very broad.

@brandon my proposed splitting option was to avoid the compatibility issues you mentioned. If we have "Earth and Planetary Sciences" while other preprint archives have just "Earth Sciences" then we will impact cross-archive searches. My personal preference is to have them distinct so that our "Earth Science" aligns with any other COS preprint system's "Earth Science". I'd rather add completely new categories than modify existing ones, which may impact future cross-archive compatibility. It also seems a bit cleaner to me to not put Planetary Science under Earth Science. For example, given a Martian geology paper, I prefer Planetary Science -> Geology over Earth Science -> Planetary Science -> Geology. Just my 2 cents. I'm happy to hear counter arguments. I don't think anything formal has been proposed to COS other than letting them know we want to add Planetary Science in some fashion.