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From: sixtysymbols
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  • Does this mean that the 'greenhouse effect' is complete junk and it is in fact a result of a perfectly natural event in the earths rotational axis

    If so then i'm no longer gonna feel guilty when i have a cigarette or run my car needlesly

  • so does that mean that the seasons gonna change, so that winter is in june?

  • 6:29 A physicist using the phrase "centrifugal forces"?

  • Great Video. Where could I buy a rotating/ hovering globe like the one in this video?

  • Clever dicks those greeks

    cheers

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  • i laugh every time i watch one of your videos because of the atlas of creation...

  • awwww he completely missed lappand by atleast an inch there =,(

  • Am I the only one who thought of dubstep after reading the title?

  • What effect does axial precesion have on global climate? Seems to me it would change the quantity of solar heating on the poles.

    

  • @jerryoven

    Realize that the *tilt* of the Earth with respect to the Sun (23-1/2 degrees) isn't changing; only the *direction* the Earth's axis points toward changes. So precession doesn't really change the climate by itself. What *does* happen, though, is that the seasons change position in the Earth's orbit.

    Right now, the northern hemisphere has winter when the Earth is closest to the Sun (and the southern hemisphere has summer). In 13,000 years (half of the precession period) ... (cont)

  • @pseudorandomly

    (cont) ... that situation will reverse. Since the Earth moves more quickly in its orbit when it is close, the southern hemisphere will wind up with less summertime heating while the northern hemisphere gets more. But since the northern hemisphere has most of the land, that change of heat balance will have some effect on climate.

  • Sure is nice to have a bunch of smart, well educated folks around to explain these complicated to us.

  • Deez niggas is smart yo

  • The Geodesic Mission did not take place in Peru, but in Ecuador...

  • Holy crap, pre-AD thinkers were clever as fuck.

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  • so..would that mean that every 13000 years the circle of seasons invert in the northern and southern hemispheres..?

  • @ambuj1991 Yes, although of course the seasons gradually shift to different times of year rather than simply switching - by about 1 day every 72 years (26,000 / 365, give or take!)

    Look at the Solstice article on Wikipedia, under 'Heliocentric view of the seasons'.

  • oooOOOH! Sneaky way to program my mind with your hypno-spirals, SCIENCE-SATAN.

  • Newton 1 Descartes 0.

  • thanks : )

  • very interesting!

    

  • my physics teacher called it angular momentum

  • how does that earth thing work... i mean how does the stand hold it up?

  • @photonman54 I'm thinking magnets

  • @photonman54 Magnets for sure.. nothing else comes to mind

  • This reminds me of why I love Physics and why I currently doing a course in Geomatics (Survey, Cartography and Remote Sensing of the Earth etc).

  • OMG What is that levitating earth device called?

    I really want one :D

  • @SuperCorey95 Its called a levitating Globe or levitating Earth, you can buy them on amazon!

  • So with something like a Powerball, are you basically pushing against the axial progression and reversing the process??

  • A little off topic, i would love if you could tell me the maker of that levitating globe. I really want to buy it. Thanks!

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  • Who in the world would give this a Dislike?

  • Guys this is sooo good. I have a extra lesson through you guys, making me smarter in my class!

    Thank you guys for exciting me! You make physics so interesting

  • Love it, thanks for putting this together! I've heard axial precession mentioned as a side note, but usually we stick to "just the facts, ma'am" because

    1. it's a slightly technical point

    2. context could be gravity, or the solar system, or Polaris, so axial precession usually doesn't take center stage

    3. It's kind of hard to understand. Like prof said, there's lots of little bits flying around and it's kind of complicated. Plus, look at that insane gyroscope! Very unexpected for me.

  • They lied in school! The earth isn't flat OR round!

  • @AlexIsSmalll Not such big of a deal... It's slightly less round than a billiard ball, so no great loss (unless your job actually involves earth measurement).

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  • Yet more proof that astrology is hogwash. Science rules!

  • Do you know if perhaps Carl Linnaeus had something to do with the whole Lappland thing?

    I'm just guessing and all but that would sound reasonable considering the fact that he did go up there.

  • @lpasepok No. It was led by Maupertius who was a bit premature in announcing that Newton was correct and Descartes was wrong. Maupertius became a French national hero because he went so for North and did experiments in terrible conditions.

  • @MrOldprof

    Yeah, pretty much assumed that I was wrong in the beginning but it would've been cool if my guess was correct.

    Thanks anyway :).

  • I shat bricks @ 1:14

  • That is sooooo coool!

  • I sincerely wish more educational shows were like this. They always seem to stifle the actual science content in favor of being "entertaining"- not realizing talented people can make science entertaining without compromising content. :) Thanks so much for all the videos!

  • @whatsarobut you're welcome... thanks for the nice comment!

  • hey brady, do you ask some of those questions for the sake of your audience or do you just get into it so much that you end up asking for your own curiosity?

  • @wvb93 a bit of both I think...

  • Show me the math please! =)

  • very cool video! could you also make one about what happens when the north and south pole switch... :)

  • I wonder, does axial procession have any effects on climate on the earth in general or in specific areas of the earth?

  • cool story bro

  • So would this have an effect on when seasons happened within the year? If the axis processes and seasons are caused by the position of the axis wouldn't this cause the seasons to very slowly alter. Does this happen? It would be too slow to notice on a personal time scale, but would it affect dating of history?

  • @arife06 He said it took 26000 years for the earth to precess one lap. Lets guess he means astronomical years, time for the earth to orbit around the sun relative to the stars.

    Then as many as 26001 tropical years would have elapsed. In tropical years the seasons are always at the same time since tropical years are determined by the sun relative position to the horizon. The sun would be highest at midsummer and lowest at midwinter for example.

    Calendars are usually based on tropical years.

  • @busanoarmy Ok I thought he said 2600 years not 26000. That clears things up a bit.

  • Please make more videos. They are short and a little bit nerdy (it's physics after all), but contain so much useful information about the world. Thank you for your effort!

  • @mrh3h we've got more coming

  • Very informative. I know that the effect of precession is very small on the human time scale but I wonder how it affects the precession of high accuracy GPS readings. Since the surface of the earth would basically be slipping one way or another at a nearly 90 degree angle to the normal rotation of the earth. I guess the whole system could be calibrated and automatically adjusted to the magnetic poles. Cool stuff.

  • @josh2utube

    i dont think the precession has any effect on the exact positioning of a gps satellite even if the precession would be way faster, say one circle in 1 month, because the satellites are bound to earths gravity so they always move with the planet. after all they are not left behind by earth on its orbit around the sun ...

  • @BurtonRGA7 True they are bound to the earth by gravity in relation to elevation but the force of rotation of a celestial body is not transmitted via gravitational waves, those remain relatively constant at a distance even if the object is rotating. By that logic the normal 24hr rotation of the earth would speed satellites up and not require you to accelerate an object to 7.5 km/s to keep it in orbit, the earth would do it for you.

  • @BurtonRGA7 And if the earth spun as fast as the sun did on its axis our year would only be 25-35 days long. Or our years would get consecutively shorter as the sun tried to accelerate us to match it axial rotation speed.

  • after watching ,,,i quite suddenly thought ...'were the Ice ages a global phenomenon?' ...in other words when one (ice age) happened 'did ice cover the entire planet?' ...is there a definitive answer?

    even in the 'Snow Ball' accounts there seems to be a number of assertions that the evidence occurs globally still there is the question as to where the plates were located in relation to each other

    thank-you for sharing this information ...some of the comment inspired by this video are remarkable

  • what is the globe sitting in in this??

  • I love sixty symbols. I should have done physics!

  • @davedupplaw it's never too late!

  • @davedupplaw now i am 10 times better even though we don't take physics at school!

  • does that mean that in 26 000 years summer and winter will be switched (january hot and july cold) :)

  • @KillaKingStyle

    no, our calender takes care of that effect so the summer will always be in july :)

    but what changes, is the position of the sun relative to the background stars.

    so the whole thing about astrology is crap because the zodiacal sings change over time...

  • @BurtonRGA7 I'm thinking you mean 'signs' ...interesting ...yes? ...how easy it is to mix up our most elemental concepts ...if we can be generous with our thinking about mix-ups then it is possible that we can eliminate words like "crap" from our thinking

    just a thought ;-])

  • @gaiagale

    erm... ok

    that was a typo, so what's the deal?

  • @BurtonRGA7 ;-]) 

  • If the speaker had elaborated on nutation he could have mentioned that the earth has to be oblate (fatter at the equator than at the poles) to spin as it does. All of the water in the oceans and the magna inside the earth dissipate energy to keep the motion stable. So, if somehow enough mass could move from the equator to the poles the earth would "flip over" and spin about an axis through the equator. The resulting climate change would likely kill most life on earth.

  • YES!

  • com'on nibiru!

  • Great video!

  • i want one of those globe brilliant i thought and this explains the moon been vertical rather than horizontal when changing well at least in my location .

  • The chief effect of precession as viewed from Earth is that the north celestial pole moves away from Polaris as the pole star. In fact, Vega was once the pole star. In 2026 (I think) the pole will be at its closest approach to Polaris, and afterwards will begin moving away from it. Obviously, the same thing happens to the south pole as well.

  • What force holds our galaxies in its point in space or are we in free fall spin out ? Just wondering.......

  • @underwood154: They are in freefall, but that doesn't negate the fact that all the galaxies in the universe are mutually gravitationally attracted to one another. The fact that gravity propagates at the speed of light complicates things at the galactic scale, and then of course there is the effects of black matter, which is thought to be gravitational in nature, and black energy, which isn't. The total effect is that the matter is attracted into globs and threads, leaving empty voids.

  • So the melting ice of the poles, and the resultant water moving to the equator region, would enhance the effect even more, causing the polar regions to get even longer sunlight through the year, which melts even more ice and so on.

    How long would you figure it would take for a great tilt, and plate shift to occur.

    I know that there are stones found in Petoski, MI, USA that suggest that that region was once a tropic region. These stones are called Petoski stones and are fosselized coral.

  • @Stormrunner0002: The world's oblateness is in balance; it can't permanently change. It might be that warmth will cause a change in that balance, but the Earth will compensate over long times by changing shape as required. Isostatic rebound, the effect that ice on continents melting away allows the ground to rise, is part of that process. The bulge will remain, as long as the Earth rotates. The sea level at the equator is about 21 km higher than it is at the poles.

  • 26.000*

  • sopwith camel

  • But doesn't this mean that one part of the earth will always be in sunlight?

  • @MrDeanage Notice that he said it would take several thousands of years (I'm not sure if it was 8.000 or 23.000), it doesn't change in one year. If it did, then yes one side of the earth would always be in sunlight OR the days/nights would last half as long incase it spinned in the other direction.

    But yeah it would be interesting to know if this actually caused a switch of seasons.

  • Look into the camera, pleeeease!

  • @HubertCumberdale22 Who: me(roger Bowley) or Mike Merrifield?

  • I posted a request for a Milankovitch cycle video months ago...I wonder if this video was partly due to my request :D.

  • @mcchuff Yes---but I had to look up Milankovitch on Google.  The real reason why I did the video was that George showed me the gyroscope used in the video and I realised that I could demonstrate how a torque causes axial precession. If you have any other suggestions please write to me.

  • will the climate of places change because of axial precession?

  • It has come to my attention that I am wrong (!!) Precession itself does have an effect on climate, though it is mild compared to the "big three". What happens is that when the pole is tilted toward or away from the sun, the seasons are more extreme (hotter summers, colder winters) that they are between those states.

  • i live in lappland, sweden :)

  • Interesting

  • do galaxies have this processional activity?

  • @Pianoguy32: In order to show precession the spinning body must be one solid piece. In a galaxy, some parts may have a precession, some may not.

  • Why cant we feel the earth spinning ?

  • @sonic003573 I don't actually know the answer but I have a rough idea, so anybody correct me if I'm wrong. But I think its something to do with the earth spinning at a constant speed, its the same when your in a car travelling at a constant speed, you can't feel your moving forward, you can only see it.

  • @sonic003573 "Why cant we feel the earth spinning?"

    What would you expect to feel? Serious question.

    This was actually a standard SAT question in a primary school near me and the answer given to the teachers was "because it is so big". At work, after discussing it with half a dozen or so engineers for about 20 minutes the only thing we were sure of was that the answer wasn't "because it is so big". Mostly we were trying to figure out what the questioner thought they "should" be feeling.

  • @chrisofnottingham im not sure just the feel of motion that all

  • @sonic003573 "im not sure just the feel of motion "

    What is that like? I really can't imagine.what you expect it to feel.

    Constant linear motion feels identical to being stationary. If you are in, say, a car you get jiggled around by bends and bumps but obviously the Earth's motion is smooth. Any centrifugal force due to the curved path manifests as a constant (tiny) reduction in weight, so you have nothing to compare it to. Do you expect to feel the wind in your face? Genuinely perplexed.

  • @chrisofnottingham i think you are right so it don't matter if we were travelling at the speed of light It would feel the same as if we were still..

  • I'm sitting about 5 kilometers from where the French expedition went to check for the flatness in Lappland.

  • Don't stop making these videos, they are extremly interesting.

  • After reading Descarte's Meditations I find it hard to take anything he says seriously.

  • does the earth inherit its non spherical shape due to its spinning or did it develop it from some other source? that is to say if the earth did stop spinning would it be a perfect sphere?

  • i want that floating globe...

  • @loserofnothing me too

  • I LOVE your videos and this one is particularly awesome ^__^

  • I want a floating earth thing.

  • strange, he refered to the moon as a planet...is it technically a planet? or more likely just a mistake?

  • 0:05 OMG MALAYSIA! That's where I am :D

  • How does this wobbling work on uranus wich is tilted almost 90 degrees?

  • @Dextomus: Yes. It precesses; the point on the celestial sphere that its north pole points to moves because of gyroscopic motion and forces.

  • A former professor acknowledged the simplification in a rotating reference frame of centrifugal force! Yay!

  • @axelasdf

    I'll have you know I am still a Professor---until 1 September when I become an Emerits Professor. 

  • @MrOldprof

    I do apologize. When I saw the video about clearing out your office, I made the wrong assumption. Thank you .

  • You ever wonder how they make satellites change their aim in space? This works.

  • I love that each of your videos gives me a little bit more knowledge in understanding our universe. Thank you for putting an effort into making these videos. Too bad not to many people are looking into this kind of stuff. Again I thank you!

  • @deadmansouls: Who's not looking into it? Don't say that to anyone working in aerospace!!

  • @puncheex many are just looking into lady gaga and gangsta rap. Subscribers:

    40,281 to sixty symbols. Subscribers:

    807,567 to meekakitty (and she is not something as commercial as rihanna or any other star)... hmmm... Just an example. Don't get me wrong. Singing is art. But slow minds tend to move away from sixty symbols' kind of vids/info.

  • @deadmansouls: All right, you (and perhaps he) are referencing the video itself, not the topic of the video. OK, his remark suddenly makes sense. Thanks for the mind-wrench - I needed that.

  • Good explanation especially using the gyro!

    I have to say.... Im SO SO SO happy to still be seeing "MrOldProf" at the start, making a cameo. Happy retirement MrOldProf; you have become my fav on SixtySymbols and Im glad you are still helping with Brady's project and keeping us crazy interwebz characters happy, entertained and edu-ma-cated! :) Best Regards, J :)

  • Isn't there some correlation between the axis wobble and the changes in average earth temperature?

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  • @puncheex That's the one I was thinking of. How the degree of the axis changes in a cycle over so many years. Thought that was what the video was about(didn't really watch it lol).

  • @12gaugebleachdrinker: No. The average doesn't change; the seasons get more extreme when the axis gets close to the axis of the sun.

  • @puncheex Yearly average, not 10,000 yearly average. Give me a break. I'm talking lifespan terms dude. No need to jump down my throat over what you(the grinch) and I feel is relevant in terms of "average temperature."

  • @12gaugebleachdrinker: I jumped down your throat? Not likely, with all that bleach down there.

    The change in climate due to precession is not anything noticeable within a lifespan. The cyclic effect goes from the mild season to the extreme season in 6500 years. It likely would take a trained scientist to detect it at the extremes.

  • @puncheex You could use to drink some bleach. Or wash your eyes with it.

  • anyone else notice the two video responses combine into one image? COMBO

  • 6:30 ...but there's no such thing as centrifugal force! (Let the nerdy flame wars begin :D )

  • @johnizzle725 Where's your video explaining your comment?

  • @12gaugebleachdrinker I didn't know I needed one? It's a common argument that "centrifugal force" doesn't really exist, whereas "centripetal" does. Feel free to wikipedia that if you need. :)

  • @johnizzle725 Potato/Patato. And I know what you meant. It's just terms dude. You must have had an overzealous science teacher who felt jaded on that subject at some point in his life.

  • Wait... I thought he was retired? Good for you professor!! Coming back and explaining the wondrous of nature.

  • @Sockheadableful He retired, but will still make videos.

  • So does that mean in 13,000 years Summer in the northern hemisphere will take place December through March?

  • That greek guy was clever!

  • @AntiProtonBoy yeah - I was blown away by that too! 150BC! Amazing...

  • how in the world does someone dislike this, you guys/girls fail science or something?

  • By far, the best explanation of axial precession that I have heard thus far! Very well done!

  • there's no such thing as centrifugal force...

    JK, loved the video. Shared it with my g/f and everybody on FB.

  • What caused earth's axial precession?

  • @catsfromhell1: Gyroscopic motion of the spinning Earth being pulled by the sun and moon, mainly.

  • @puncheex Thanks.

  • Does this mean that every 13,000 years the seasons shift?

  • @McC1oudv2 I'm curious about this too. I think that this means every 13k years we have an ice age. No?

  • @McC1oudv2 Yes and no... nobody would likely notice a difference, but technically season conditions which exist for the earth while it's on one side of the sun, would become reversed.

  • @McC1oudv2: No. What happens is that, as a consequence, the dates for the equioxes and solstices will shift around a 13 000 year cycle.

  • @McC1oudv2 no but the pole star changes.

  • @McC1oudv2 I wouldn't say that they shift, there is a slightly change on the axis degrees, that graphic is just illustrative, not enough to shift them. But yes, probably there's some kind of temperature change, Just an opinion. :)

  • @McC1oudv2 no it means that ufo disclosure will happen within the next two years.

  • @McC1oudv2 +- that 8 year wobble.

  • @McC1oudv2

    No, the seasons won't shift, because our calendar is based on a tropical year, which is defined as the time from vernal equinox to vernal equinox, and this takes precession into account. By contrast, a sidereal year is the time taken by the Earth to orbit the Sun once with respect to the fixed stars. Google "tropical year" and "sidereal year".

  • @Pulsar89 Thanks for answering this I was about to ask the same exact thing.

  • @McC1oudv2

    No. the seasons shift twice a year.

  • @McC1oudv2 not if we keep having leap years.

  • Centrifugal? :o

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  • Bah! I still don't completely understand rotation. It's frustating!

  • Dear Sixty symbols,

    I disliked this video because you completely overlooked that ancient civilizations from over 10,000 years ago have been measuring the procession of the equanoxes and building HUGE structures like the pyramids with measurements that would NEED to have knowledge of that 26,000 years cycle and the procession of the ages. Look at ANY ancient civilization past 10,000 years old like the Olmecs before the Maya or the indian civilizations that spawned the vedic texts. LRN2RESEARCH

  • @RAV3xBinG3 I don't know of a single ancient building related to the PRECESSION of the equinoxes. There are of course many related to solstices (the shortest and longest day of the year) and there may be some related to equinoxes (the days that have the same length than their nights). However, I doubt there may be too many buildings related to the precession of the equinoxes. Being a cycle of 26000 years, I doubt many ancient civs would have understood it, really.

  • I bet he steals the globe when he retires.

  • Woohoo

  • Is this why spinning tops start to wobble as they slow down? As the forces become unbalanced?