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Has Earth’s inner core stopped its strange spin?
- puffoflogic 4y agoI think something is being poorly explained, because that's a lot - a very big lot - of angular momentum that's got to go somewhere or come from somewhere.
- deleted 4y ago[deleted]
- mcdonje 4y agoSo, I think the headline is a little misleading. The article talks about the core spinning in relationship to the earth's spin. So, the disputed claim is that it has been spinning faster than the earth, and it's going to be spinning slower than the earth. It's not stopping or reversing. As for what would cause it to slow down or speed up with relationship to the speed of the planet's spin, they just say "magnetic and gravitational forces", whatever that means.
- sliken 4y agoWell keep in mind that it's not the rotation that's stopping, or reversing. So far there's debate, but the data supports the core is spinning 0.1 degrees per year faster or slower. Other researchers think it's changes in the surface of the core (not the rotation). What we do know is that earthquakes show waves that travel slightly faster or slower than we'd expect if the core's rotational speed was constant with the rest of the planet. But overall it's nearly in the noise compared to the other energies involved. The flows involved are turbulent and move like fluids, but at the pressures and viscosties involved they change rather slowly. Some models show it switching from slightly faster (0.1 degrees per year) to slightly slower ever 35 years or so.
- luxuryballs 4y agoif the waves don’t behave how we expect maybe we just don’t understand how we should expect them to behave, it seems like a lot of assumptions have to be made in order to make any broad conclusions from such readings
- sliken 4y agoSure, it's under heavy debate. While the idea or the planet spinning at different speeds weird to think about, the physics do work out. After all not like the atmosphere spins at exactly the same speed as the planet. Why should the core of the planet in a pool of magma spin at exactly the same rate? The discussed difference is only 0.1 degrees per year, on the surface of the planet that's only 7 miles. So what's under the surface today might be 7 miles different in a year. The movement that deep is quite a bit less than 7 miles since the circumference at that depth is much less. Additionally it's not rock and dirt at that depth, but a liquid magma with an average speed of a foot a day is not too surprising. Humans think of these things as constant, but the length of the day and the distance of the moon are changing because tides are transferring rotational energy of the earth into the moon. Said forces aren't directly impacting the spin of the core, so it might well be catching up and oscillating around the speed of the earth's rotation every 35 days.
- someweirdperson 4y agoMaybe earth is a cat. They can flip themselves around while in the air without exchanging momentum with anything.
- rolenthedeep 4y agoNot a geophysicist so I'm just spitballing: the earth's magnetic field is mainly generated by the motion of the liquid outer core. I think the hypothesis here is that the magnetic field is exerting some force on the inner core causing it to slow or speed up. But yes, there is an absolutely absurd amount of energy in this scenario. On the scale of "let's stop the moon spinning" big. Even at the scale of slowing from one degree of rotation per year to zero degrees over a few decades, it's a lot of energy. And that's not even counting all of the other energy drains in this system, like turbulence between the outer and inner cores from rotating at different rates, or the magnetic field of the inner core fighting the outer core. The amount of energy involved is just absolutely bonkers.
- forgotpwd16 4y agoTopic reminds of film The Core in which the core has stopped rotating initiating a series of apocalyptic phenomena. (And in a Hollywoodian fashion the solution is to release a few nukes in it to restart it.)
- amelius 4y agoThat was a really bad movie.
- ChuckMcM 4y agoYes, but I know a group of geologists that made a drinking game out of everything the movie got wrong about geology. They are always quite drunk by the end!
- pchristensen 4y agoSounds dangerous!
- wilg 4y agoIt’s absolutely amazing though.
- dylan604 4y agoabsolutely amazingly bad though. i recently (within a few weeks) watched this from beginning to end, and holy cow was i not impressed. to have so many actors of high report to end up such a horrible movie.
- amelius 4y agoThey wanted to make a disaster movie, and the movie indeed turned out to be a disaster :)
- bob1029 4y agoReally bad, but I absolutely love trash like this for some reason. I can watch movies like The Core over and over.
- aerophilic 4y agoQuestion: Is anyone familiar/aware of the possible implications to the global magnetic field? I know magnetic north has been slowly shifting… but as I understand it, this currently involves changing the values on runways (the number on a runway is the degrees per magnetic north)… but that is pretty much it. What happens if magnetic north becomes magnetic south? Is there anything beyond the obvious (compasses and things that rely on compasses) that would be impacted?
- greenbit 4y agoFrom what I've heard, the problem is that the reversal can take a few years, during which there may be almost no field strength. That, and there's no guarantee about exactly where the new poles will develop, apart from them appearing at relatively high latitudes.
- xattt 4y ago> during which there may be almost no field strength Does this increase the susceptibility of the Earth to the effects of solar wind, such as increased radiation at sea level or atmospheric erosion (like on Mars)?
- andai 4y agoSo during this time, earth would be (more) vulnerable to solar flares and other radiation?
- deleted 4y ago[deleted]
- someweirdperson 4y ago> The only way out of the morass is to wait for more earthquakes to happen. Modern sensors might be sensitive enough that a nuke could provide sufficient stimulation?
- rolenthedeep 4y agoSure, and our radiation sensors are delicate enough to tell exactly how many people get poisoned by the fallout!
- thombat 4y agoAn underground test will be the best source of data, so no fallout as such.
- clbrmbr 4y agoIndeed, the article mentions using data from nuclear tests. Presumably “we just need to wait” includes waiting for a nuke to detonate somewhere. It’s not the 1960s anymore. I don’t think setting off a nuke as an intervention for measuring the earth’s core is a very popular idea these days.
- roywiggins 4y agoThe hard part, apart from obtaining the nuke, is getting IRB approval. (the article notes that they did use historical seismic data on nuclear tests to probe what the core was up to in the 60s)
- peter303 4y agoRussian seismologists made artificial earthquakes up to M6 with nukes in the 1950s and 1960s under its peaceful nukes program. These data remain some of highest quality seismic data ever recorded.
- version_five 4y ago“I keep thinking we’re on the verge of figuring this out,” says John Vidale, a seismologist at the University of Southern California in Los Angeles. “But I’m not sure.” I wish we saw a lot more of this and less of the "science tells us" stuff that seems to dominate reporting now
- munchler 4y ago> less of the "science tells us" stuff Such as? Seems to me that good science does tell us stuff, and also admits when it doesn't know.
- XorNot 4y agoThe OP is complaining about mainstream science reporting, in comments on an article being posted by Nature - which is literally the absolute top of peer-reviewed journals. Which is to say, it suffers from the same fallacy as when people complain about Hacker News' collective opinion as though a collective anything with voluntary participation is going to be in anyway consistent.
- bawolff 4y agoNature the journal and nature science news articles are pretty different things though.
- petschge 4y agoAt least in my field the running joke is "it was published in Nature but it still might be right". Because Nature above all wants to be high impact. And you get that by publishing the controversial or unexpected findings. In other words the ones that are most likely to be wrong.
- dsfyu404ed 4y ago>Which is to say, it suffers from the same fallacy as when people complain about Hacker News' collective opinion as though a collective anything with voluntary participation is going to be in anyway consistent. It might not be consistent but even Ray Charles can tell you where the bell curve roughly centers for any given topic.
- escapecharacter 4y agoWith coordination, I believe several high-level Hamon users could undo this problem.
- sophacles 4y agoWe took out all the oil, and the dynamo ground to a halt. Neat.
- toomanyrichies 4y agoI’m confused, are you implying one caused the other?
- jacobsenscott 4y agoOf course. The oil lubricated the dyno.
- anemoknee 4y agoThe dinos lubricated the dyno.
- nuccy 4y agoThe size of the Earth is incomprehensible - if Earth was a basketball ball in your hands, all the mountains and deepest trenches of the oceans would make the surface imperfections of under 1mm (1/20 inch) high/deep. The average ocean depth of 3km would be 3.7 times less than that - exactly the height of basketball bumps. Earth's atmosphere would reach 1cm (half an inch) but 3/4 of its mass would be under those imperfections. The atmosphere is 5 times heavier than all water combined, but its mass is just one millions of the total Earth's mass. Screwing up atmosphere is "easier", especially since burning transforms dense (solid and liquid) C-H containing materials into much less dense gas.
- senectus1 4y agoand yet we still manage to ruin it for ourselves in such a small amount of time. We need to do better.
- deleted 4y ago[deleted]
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- nikhilgk 4y agoIt was surprising to come across an article on geological or planet-scale phenomena that did not mention human activities as a contributing factor to the changes being discussed. Effects of Anthropocene are still only skin deep.
- LASR 4y agoGoes back to the George Carlin skit where he more accurately points out that human factors around “damage” to the Earth really only damages humans. We may cause some extinctions and such, but overall, the Earth and life will go on with or without us.
- elevaet 4y agoThe damage obviously goes beyond humans (for example coral reefs are getting decimated), but it's true the planet has endured far greater assaults in the past, and life has marched on. Environmentalism is Humanism in disguise. The risk is that we'll soil the crib and turn the planet into a hell-hole for future generations of humans.
- xeromal 4y agoAKA Don't shit where you eat.
- willis936 4y agoWell, we haven't started drilling mantle-depth geothermal vents on an industrial scale yet. That day might be coming though.
- TheRealPomax 4y agoScience article titled as a yes/no question? Then the answer is almost certainly "no", because if the answer was "yes", the statement itself would have generated more than enough clicks. So, reading the article, the answer is in fact "We don't know. Nor is there enough evidence right now to even guess" for that perfect time-wasting double whammy. Nice! What lovely click bait.
- chrismarlow9 4y agoAnd if the answer is "yes" you can always find someone in the comments who wrote a PhD dissertation on the topic that tells you the answer probably isn't "yes".
- layer8 4y agoI appreciate those question marks in titles, because they let you know right away that the answer is “probably not” (aka Betteridge's law of headlines).
- RektBoy 4y agoI watched "The Core" yesterday, wtf.
- ThinkBeat 4y agoHow certain are we (current science) that our conclusion regarding the composition / architecture / structure of the inner /deepest part of the planet? From what I have read, we have not had any probes too far into the earth. I remember someone saying that we know more about space than we do about the earth. I dont know if I should have listened to the guy. I do understand that the article references distributed readings over long timespans of seismic data that allows scientists to establish the current view.
- wongarsu 4y agoWe have a better idea than at any time before. But we only really know about large-scale structures, and have well-justified guesses at the materials involved. The deepest borehole we ever made is only about 10% deeper than the Mariana Trench, not even close to getting through the crust. Most of our data is either from seismic measurements, which are useful because shockwaves travel at different rates through different materials and can be reflected at material boundaries, or from neutrino measurements.
- peter303 4y agoSeismic waves and ultra high pressure mineral lab experiments. Seismic waves suffers from antenna limitation artifacts with the 70% ocean barely instrumented. A French group launches torpedo seismometers for months at a time to fill in gaps.
- nprateem 4y agoStatistically surely this is highly unlikely unless changes happen frequently. I mean, in the 4 billion years or whatever the Earth has been around for, it just so happens to choose to change its spin in the couple of decades in which we develop tools to measure it?
- delecti 4y agoEarth's magnetic field has reversed multiple times in the past (the graphic on Wikipedia shows ~20 in the past 5 million years). I don't think we knew why, but this could be it. Given the frequency of it, this isn't likely to be catastrophic from a biological perspective, but might cause havoc technologically. https://en.wikipedia.org/wiki/Geomagnetic_reversal https://en.wikipedia.org/wiki/Geomagnetic_reversal
- losteric 4y agoDid you read the article? The article mentions switches between super- and subrotation have occurred within just the past 50 years. So, yeah seems to happen pretty frequently. Note noting is talking about the cessation of rotation. The article is very clearly about the "strange spin" discrepancy between outer and inner core.
- peter303 4y ago2022 or 2023 might need to SUBTRACT a leap second because the whole Earth's rotation has mysteriously sped up about a millisecond. Since the definition of the year switched to atomic seconds some years ago, they previously had needed to ADD leap seconds to sync to the astronomical year. Earthquakes, weather, ocean circulation can change length of day. Perhaps the core rotation changes may be affecting the whole Earth too.
- entropicgravity 4y agoIt's probably just resting.