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In contrast to Earth, Mars's middle atmosphere appears driven by gravity waves (phys.org)
67 points by wglb 15 hours ago | hide | past | favorite | 21 comments






> Not to be confused with gravitational waves from massive stellar bodies, [gravity waves] are an atmospheric phenomenon when a packet of air rises and falls due to variations in buoyancy.

For those similarly confused by the title as I.


I used to thing programmers were bad a naming things until I became interested in physics.

Related to this discussion, astronomers’ usage of ‘metal’ is a fun example.

"it can't be that bad, can it?"

> astronomers use the word metals as convenient shorthand for all elements except hydrogen and helium

what, ok


To keep on topic, that makes Earth's and Mars' atmospheres consist of metals.


Isn't there predicted to be liquid metallic hydrogen in Jupiter's core?

Metallic as an adjective, behaving like a metal - due to the insane pressures. Different usage of the word "metal".

Yeah, fun, right?

I've looked up why before, tldr it's just because historically astronomers have never had to care in any detail about chemical reactions (this is not strictly true of course, but somewhat close for at least a large subset). So they just need a term for "crap that came from stars".


Reminds me of: https://xkcd.com/2205/

Eh, that grosses over the defining difference that hydrogen, helium, and a little bit of lithium are everywhere everywhen all at once because of The Bog Bang, whereas everything else is concentrated due to being produced in supernovas and neutron stars.

And musicians!

Salts in chemistry too

Worse than math, where set theory, type theory, group theory, and category theory all exist and refer to barely-related things?

Wait until you spend time learning probability, or worse, biology.

One type of gravity waves can be seen on Earth where its atmosphere meets large bodies of water. These are commonly known as ocean waves.

I am cynical but, I am pretty sure the ambiguity was intentional

Seriously, what a dumb title. Anybody who knows what gravity waves are is gonna read it and go “what?? no.”

You are confusing gravity waves and gravitational waves.

Gravity waves are waves where the restoring force on some medium comes from gravity. Waves you see on the surface of water, for example, are gravity waves.


As always - relevant XKCD - https://xkcd.com/2340/



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