you, too, can be a lava monster if you want to

[kaberett]

Friends Who Shall Remain Unnamed (but are welcome to identify themselves in comments) decided, earlier, that it would be hilarious to direct my attention towards this tiktok. It's captioned and audio's unnecessary, but the content goes like this:

So, somebody asked me a seemingly very innocuous question, "Is ice a rock?" and it is. Geologists say it is. Then someone else asked me a question that I knew the answer was going to be no to, "Well, if ice is a rock, is water lava?"

I was like, "No. There's no way this is gonna be-"

I looked it up and I'm reading about it, and it's like... it kinda is! Lava is any molten rock that comes out of a terrestrial planet. Now, molten means liquefied by heat. This is- *science frustration* I don't know what to believe anymore. Ice is a rock, water is lava, and you are a lava monster... I guess!?

Now. You need to understand, this is a group of people who have previously witnessed what happens when someone innocently says "hey, kab, can you... explain... this science fiction? it's saying this planet has a core made of low-density non-conductive metal--" i.e. WHAT THE FUCK DO THEY THINK A "METAL" IS THEN (tl;dr "electrons go whoosh") (honestly it took me an embarrassingly long time to hit the AND ANOTHER THING-- of "if it's low density it wouldn't have segregated to form a core--")

... so the betting pool was apparently 50-50 on whether they were going to get, you know, that kind of reaction or, instead, the one of OH BOY LET ME TELL YOU ABOUT THE EIGHTEEN DIFFERENT CRYSTALLINE FORMS OF ICE AND ALSO EUROPA'S ICE VOLCANOES--

... but they got the latter, and now you do too.

[this has been a Fun Geology interlude in your scheduled programme of Thesis Angst, sponsored by--]

Comments

[hilarita]

Anyway, everything other than H and He is a metal... if you're an astronomer.

*watches chemists crying in a corner*

[kaberett]

oh cool, what definition do you lot use?

[hilarita]

It's an interesting question...

Astronomers pretty much universally define anything beyond He as a metal.
Though this depends a bit, usually this comes up in terms of low and high metallicity.

Low metallicity *usually* means iron-poor, relative to the abundances in the Sun. Sometimes it means low abundance of things other than H and He... But then astronomers shouldn't be allowed to name or define things (see the classifications of stars into M, N, O types, etc., and the mess that is SuperNovae).

Obviously computer programmers and engineers tend to use definitions of metal that don't include the Noble gases... and silicon...

I'm just glad it doesn't crop up as a problem very often.

The more common problem is that radio astronomers (esp. low frequency astronomers) talk a lot about uv. This is not ultra-violet light, but a Cartesian co-ordinate space. And that a lot of radio astronomers talk about L band (or whatever), rather than using Hz. This is intensely annoying for those of us who haven't memorised the band definitions, which are *intentionally confusing*. L band etc. were used during the Second World War as security through obscurity, so you could say "switch to N band", and rely on the fact that the other side didn't have a clue what N band was. So they're deliberately in a random order, and it irks the hell out of me that these descriptions are still used when there's no reason to do this any more! Use Hz!

[lebannen]

Ohhh, is this the same thing as radars coming in X band and S band flavours? And one of them is 3 cm and the other is 10 cm and it makes NO SENSE which is which, so I consistently forget?

Like, every so often I have been asked, and all I can ever say is that we have two! They are both the same! and it's the kind that SARTs show up on!

(A SART will only respond to a 9 GHz X-band (3 cm wavelength) radar. It will not be seen on S-band (10 cm) or other radar. And I will promptly forget that again in about five minutes.)

[hairyears]

Which is hugely entertaining, because metallic Hydrogen is A Thing.

[hilarita]

Sssh. Don't mention this to astronomers.

[lireavue]

*fond and still giggling* And thank you for reminding me how UTTERLY BADASS Europa is, as I had temporarily mislaid that brain-file.

[alexseanchai]

*grinning*

[fyreharper]

:D

[serpentrose]

Thank you for sharing this - it made my day.

[steorra]

:-)

(Europa picture, of course.)

[steorra]

(Also I would definitely have caught the problem with a low-density core but I'm not sure I'd have caught the problem with a non-conductive metal.)

[kaberett]

hilarita above notwithstanding, for most purposes metals are defined by the kind of atomic structures and electron-sharing they do -- very roughly, you've got ionic bonds (electrons transferred between ions, and they're then attracted by their opposite charges); covalent bonds (electrons are shared between atoms in specific bonding orbitals, which get a bit weird in the context of e.g. benzene but the concept fundamentally holds); and... metals, where you smoosh a bunch of different atoms together and they just arrange themselves in a lattice of arbitrary size and you wind up with an "electron sea", with electrons perfectly happy to just sort of float around in the vague vicinity of any of the contiguous atoms. That is, one of the defining features of a metal (again, with an apparent exception for astronomers ;) ) is that electrons are free to just go for a wander, which means that if you apply a charge across the metal they will go for a wander, i.e. by definition metals are conductive!

[davidgillon]

AND ALSO EUROPA'S ICE VOLCANOES--

Hmm, he says innocently, does this mean mud from a mud volcano is lava?

;)

[kaberett]

UNFORTUNATELY, AS SOMEONE WHO HAS BEEN CITING ONE OF THESE DAMN PAPERS A LOT RECENTLY, THE ANSWER IS YES.

[davidgillon]

Wow, wasn't expecting mud volcanoes to have featured in thesis swamp!

(Though mud, swamp...)

[kaberett]

Unfortunately the ones around the Mariana arc have been studied in ways that are Relevant to That Paper, which is ch3 of the thesis...

[recessional]

“Proton ordered semetric ice “ is the name of my next band.

[silveradept]

This sounds like one of those things where we have to remember that the categories that we use for classification are actually a lot broader than we think they are. And I'm also imagining one of those "purist, neutral, chaotic" 3x3 grids with rocks and lava as the two axes.

[wordweaverlynn]

I would be ecstatic if someone made such a grid.

*raises hand*

[vass]

I for one am delighted to learn that I am a lava monster.

Also, ICE VOLCANOES.

*Counts the fingers on the raised hand*

[hairyears]

DOOM MONS.

There is an actual Mount Doom!


https://en.m.wikipedia.org/wiki/Doom_Mons

[cesy]

:)

[cloudsinvenice]

I am so happy to learn that ice volcanoes exist!

[ludy]

John Green from the TikTok was a guest at the HPST summer camp and gave relationship advice to various Hogwarts inhabitants - including answering a letter i wrote in as Winky the HouseElf*. He was both hilarious and very sensible...


*she felt torn between HouseElf culture and her partner Dobby's FreeElf Activism

[swingandswirl]

Noooo. Bad. /makes sign of the cross/

Thanks for the link to Europa's ice volcanoes, though, they are awesome.

[kaberett]

lava monster

[hairyears]

Presumably - or at least, plausibly - there are volcanoes spewing out the other common hydrides, too: liquefied methane ice, and ammonia.

Or even longer hydrocarbons than methane: if they can rain out of the atmosphere and form lakes on the surface of Titan, they can melt in the subsurface layers of accreted carbonaceous chondrites that orbit Jupiter or Saturn.

[hairyears]

Also: I am earwormed by Dolly Parton singing "Tholine, Tholine, THO-LI-II-INE!" and now you are, too.