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The ingenuity (and accumulated knowledge) of people never stops amazing me. "Well, we can't actually drill into Mars to see what it's made of, so let's slap a m
by kaycebasques 3y ago
The ingenuity (and accumulated knowledge) of people never stops amazing me. "Well, we can't actually drill into Mars to see what it's made of, so let's slap a marsquake detector on the surface and we'll measure seismic energy from meteor impacts to figure out what this bad boy's guts are made of." Of course no NASA person actually talks like this; I have been reading too much Heinlein.
Also, they use the term "marsquake". Never stopped to think about how geocentric the term "earthquake" is!
- KingLancelot 3y agoIt’ll blown your mind when you realize what “Geo” means. (Geo is the Greek word for Earth)
- qiine 3y agomoonquake exist too ! https://edition.cnn.com/2023/09/14/world/moonquakes-apollo-17-scn/index.html https://edition.cnn.com/2023/09/14/world/moonquakes-apollo-1...
- kaycebasques 3y ago[flagged]
- wongarsu 3y agoAs the article shortly touches on, it's how we know what the earth is made out of too. Our deepest borehole reaches 0.2% of the distance to the middle of the earth, most of what we know is instead from measuring seismic waves from earthquakes.
- MagicMoonlight 3y agoMy question is, if we were to dig a hole to the centre and carve out a sphere there, would the very central point have no gravity? My thinking is that the mass is in all directions so the gravity would cancel out in the middle. You’d then have an inside surface you could run around on which would have gravity.
- hanche 3y agoYes! In fact, as you go down the borehole, gravity will decrease linearly, until it reaches zero at the center. Strictly speaking, not quite linearly, since the earth’s density is not uniform. Thinking of the earth as made up of concentric shells, it turns out that once you’re inside a spherical shell of uniform density, that shell contributes zero to the gravitational field. Outside of it, OTOH, the shell produces gravity as if all its mass were located at the center.
- positr0n 3y agoOne of my favorite fun facts is that if you were to dig a frictionless borehole to the other side of the world, you could hope in, be accelerated towards the center of the earth, decelerate on your way up to the other side, and pop out with 0 velocity 42 minutes later. Now, this is the fun part, the 42 minute time frame is true for using gravity to coast through a straight hole between any two locations on Earth's surface! (Assuming a perfectly uniform density sphere and no friction on your journey of course)
- hanche 3y agoIt’s fun to think about, but frictionless means you’d have to pump out the air. So you’d need to wear a space suit, and heat shielding. It’s kinda hot down there.
- gilleain 3y ago"... For here, at the very center of this watery globe, there seemed to be no gravity. There was collossal pressure, certainly, pressing in from every side, but one was in effect weightless ..."
- HerculePoirot 3y agoIn French "to land" is "atterrir" (to earth). So we have "alunir". >The eagle has mooned ! https://en.wiktionary.org/wiki/amarsir https://en.wiktionary.org/wiki/amarsir
- tomrod 3y agoI love this in so many ways!
- HerculePoirot 3y agoWait there is more, a water landing is https://fr.wikipedia.org/wiki/Amerrissage https://fr.wikipedia.org/wiki/Amerrissage (mer = sea) On Titan, this could be called an améthanissage (for methane).
- School-Cotton 3y ago“earth” (with a lowercase letter) means roughly the same thing as ground, land, soil, etc, just like “terre” in French.
- hinkley 3y ago'right' and 'droît' work the same way too. Right as in direction, right as in ethics, and right as in civics.
- feoren 3y agoSome people call Hacker News the "Orange Site", but of course that's way too fruit-centric, so we shouldn't call it that -- the website banner is not actually a citrus fruit at all! Or can we just accept that orange-the-color is a fundamentally different idea than orange-the-fruit, despite the fact that the former is named after the latter? Can we accept that "earth" can simply refer to the material that makes up the hard surface layer of a planet, as a different idea than "Earth" the planet after which it's named? Is that OK? Do we really need to come up with a new word for "Solar Power" if the power comes from a light source other than our own sun? Can we call the large-scale geoengineering of Mars "terraforming", or must we insist that it's "marsaforming" (and not "geoengineering", but "marsoengineering")? Can we call something "romantic" even if it isn't actually written in Latin ("from Medieval Latin rōmānicē, Vulgar Latin rōmānicē (“in the Roman language”, adverb"))? Is that OK with everyone? It's a damn earthquake.
- barrysteve 3y agoOnce Mars is settled/colonized/freedom I'm sure political ambivalence will encourage people to rename earthquakes to marsquakes. An earthquake on Mars very quickly becomes the local Martian government's problem when it is insanely expensive to fix.. and the vocab would follow..
- austinjp 3y agoThis is reductio ad absurdam. Planetquake. Or just quake. Incidentally, Sol isn't an 'official' name for our sun. The term 'solar power' is more like a brand-name that's been genericised.
- burnished 3y ago..how did the words 'marsquake' and 'geocentric' set you off so badly? None of your examples even loosely fit the mold, 'terra' and 'geo' don't refer to a specific planet in this context at all. Marsquake is a fun word. You can also call it an earthquake and no one will bat an eye.
- ChainOfFools 3y agoI'm not sure why I agree with the op, but I do. I think it has something to do with the fact that this convention of planet prefix, and geological activity suffix is not going to work well at astronomical scales. Epsilon-eridani-c-quake is kind of a mouthful, no? It could be argued that doesn't work very well on a human scale either. after all when there's an earthquake, barring a civilization-ending apocalyptic situation, it's not the whole Earth that's quaking (at a human scale perspective), but rather a localized crustal region of it. A patch of earth (lowercase).
- pcthrowaway 3y ago> Of course no NASA person actually talks like this Are you saying "The Martian" was inaccurate?
- archiepeach 3y agoOne could also feel a moonquake while looking at an earthrise.
- thaumasiotes 3y agoHow would one view an earthrise?
- _moof 3y agoBy going to the moon.
- thaumasiotes 3y agoDid you miss a step? The moon doesn't have earthrises.
- _moof 3y agoomg, I'm an idiot sometimes. It's a wonder they let me anywhere near spacecraft.
- deleted 3y ago[deleted]
- dplavery92 3y agohttps://en.wikipedia.org/wiki/Earthrise https://en.wikipedia.org/wiki/Earthrise