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At what speed are we moving through space?

  1. Oct 6, 2012 #1
    If Earth rotates on its axis, and revolves around the sun; and the sun revolves around the galaxy..

    -Is it possible that the solar system rotates on its axis aswell?
    -Is is possible that our galaxy revolves aroundd something too?

    -Is it possible that all the system, and/or one of its elements, is moving in any other non-orbital/non-rotational direction?

    -What would be the total max, min and average speed sum that we in earth are subjected to? (I guess it is variable given the fact that they are vectors with different and variable directions..)

    -What effect does that speed have on space, reality, matter, time, the fractal nature of universal chemistry (as experienced on earth), or existence itself?

    Thank you ≈)
  2. jcsd
  3. Oct 6, 2012 #2
    In the latter half of the 19th century various attempts were made to measure the speed of the earth relative to the 'standing still' space through which it moves. They failed to detect any motion at all. Not even 6 months later when the earth had reversed direction about 180 degrees and by an amount that was detectable given the precision of the measuring instruments. As a result of these failures and other considerations, A. Einstein proposed that there isn't any 'standing still' space, (aka aether) and made quite a name for himself in the process.
  4. Oct 6, 2012 #3
    Thanks for the thought :)

    If i`m not mistaken, wheter ether exists or not is a matter of controversy, and is something for wich the views has changed over time...

    Sometimes the general scientific view say it exists, sometimes says it dosent.. and I guess it also depends on a given particular point of view, perhaps out of necesity, when checking new theoryes or models in any field..

    But, what I guess is not a matter of controversy is the fact that we are moving!

    Because we are, arent we?

    Then in relation to a hypothetical still point, at what speed do we move?

    Or maybe we should relativize it from a higher level standpoint (universe, or galaxy group), and then go down to the smallest level, the still point, and add the global galactic or galactic group, speed to it..
  5. Oct 6, 2012 #4
    Since you can't measure the speed of the earth relative to 'standing still' space, you must measure it relative to some other object. If you use a galaxy group, a problem arises because our speed relative to some of the galaxies in the group will be different from our speed relative to others. However, you can overcome this problem by averaging the speeds. You cannot use the universe because, like a galaxy cluster, it is made of many objects moving in many different directions. When you average out the speeds in this case, you obtain the result that the earth is stationary, the speeds average out to zero. You can't go down to the smallest level, the still point, because, as I mentioned, attempts to do so have been made and all have failed.
  6. Oct 6, 2012 #5


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    It's not a controversy in modern science. Current theories preclude an ether.
    Motion is entirely relative. There is no "still". There is a reference frame in which we aren't moving all the way up to reference frames where we are moving at near light speed. All are valid.
  7. Oct 6, 2012 #6

    Okay, so it seems that beyond galactic level it is very hard to calculate relative speeds, much less absolute speeds..

    Then maybe we should start by determining our speed on this galactic level...

    We could use an object here on earth, and the galaxy as hypotetical still point.. or we could use ourselves, cause what we want to know is the speed to wich we are traveling... in this case, the speed we are travelling at in relation to the galaxy or the galactic level..

    We know at what speed earth rotates (and us in it), and at what speed the earth revolves the sun; we also know at what speed our solar system revolves the galaxy do we? (iow galaxy size, and galactic year duration)

    then how much is that in max/min or average terms?

    After that is determined, we could start considering relativizing it to higher levels, like galaxy cluster, and cluster of cluster, and then maybe the observable universe.... and I guess after all that we could start thinkin about hypothetical still points....
    Last edited: Oct 6, 2012
  8. Oct 6, 2012 #7
    If I understand what you are asking correctly, the sun (and solar system) orbit the galaxy at a relative speed of 792,000 km/hr. With respect to the CMR we move at a speed of around 2.1 million km/hr

  9. Oct 6, 2012 #8
    I'm not sure you understood what I wrote before. By averaging the speeds relative to the galaxies within a cluster, you can measure speed relative to the cluster By averaging the speeds relative to each cluster, you can measure speed relative to a cluster of clusters. But when you average the speeds relative to all the objects in the universe, you get zero. As I wrote before, scientists have been thinking about hypothetical still points for over a century. Science is about measurements, and all attempts to measure speed relative to still points have failed. Do you understand what I mean when I say that scientists have already carried out your program?
  10. Oct 6, 2012 #9
    Hey thanks, good data!

    I will read through it asap..

    With this at least it seems possible to calculate our max/min/average speed in relation to the galaxy..

    I will try to calculate it, but im a negative googleplex when it comes to maths, or as we say in Spain, a zero on the left; so if this will be too easy for any of you to calculate, please delight us!

    Ok now I see better where youre going.. sorry, English is not my first languaje..

    -I dont have any program that i-m carrying out, I just had some questions and came here cause it seemed the appropiate place to ask them..

    As you can see JonDe made a good contribution with that data, with wich we can try to understand more...

    -I didnt knew that science has determined that when you average the speeds of all objects in the universe, you get zero.... It´s a beautiful idea.

    Thats why i come here to ask!

    But is it the speed of all objects wich becomes zero in relation with themselves? the universe? the still dot?? or is it our speed wich becomes zero??

    -I wonder tho, how far you can calculate (before getting to that zero), simplifying or ignoring the little perturbances that can exist on a more local level (like other solar systems influence on our solar sytem)... or even takin em in account!

    I dont think it will be too hard for a computer to do a little realtime simplyfied model of rotating and revolting dots, in wich each dot represents a new level.. like a dot for earth, wich rotates to certain speed and revolts another dot wich is the sun, then the galaxy center...

    (i wonder if at that point little perturbances does exist anymore?)

    anyway, you could then make all those dots revolt around another, wich will represent the galaxy cluster, and so on...

    it could even have realtime speed counters of any dot in any threedimensional direction, or even a dynamic average sum of speed vectors in all directions that a particular dot could have...

    all in relation to the original dot, Earth; or us if we added the earth rotation speed to the final result...

    in the end is all numbers, it will not need to be 100% real cause for that we have reality itself, and no machine can equate that... but by grouping things it is possible to get an idea...

    yet, to what level? when does all it become zero?

    PS: would realtime mean no absolute averaging is necesary, since it will be a dynamic model...??
    Last edited: Oct 6, 2012
  11. Oct 6, 2012 #10
    Thanks again JonDe, a lot can be taken from the link you posted!

    Earth: rotation 1600 km/hr, orbit around sun 107.000km/h

    Solar System: deviation towards Lyra 70.000km/h, rotation around galaxy 792,000 km/hr

    Galaxy: movement 2.1 million km/hr

    So without taking on account the deviation towards Lyra, and considering that everything rotates in the same direction, i get:

    fastest: 1600+107000+792000+2100000= 3000600km/h

    slowest: 2100000-(107000+792000+1600)= 1199400km/h

    Fastest will be precisely in the exact instant when: you stand on earth ecuator, and its rotation direction matches the same direction as its orbit around the sun, wich matches the sun orbit around the center of the galaxy, witch matches the general direction in wich the galaxy is moving...

    I-m really unsure about the slowest, perhaps you could help me out here.. but anyway thats a lot of difference!!

    i know, its all bogus speculation, and i guess this will hardly ever happen in our lifetime, or even in the solar sytem-s lfetime... but is an amusing thought nonetheles :P

    Or maybe thats what will happen on 21 December when the Mayan calendar ends... lol
    Last edited: Oct 6, 2012
  12. Oct 6, 2012 #11
    When scientists measured the cosmic microwave background radiation very accurately, they noticed it was slightly warmer in one direction and slightly cooler in the opposite direction. That gave both a velocity and a direction to the earth's motion.
  13. Oct 6, 2012 #12
    I think to really understand it you are going to need to learn a bit more about relativity. You are using a few terms that don't really apply. "still dot" and "realtime" aren't really very good concepts in general relativity.

    I'm not really sure what you mean by "realtime", who's real time? Time is dependant on motion and gravity. The further from the source of gravity you are the faster time moves. GPS satellites have to be configured for time dilation otherwise they wouldn't work. Time really does move faster in low orbit.
  14. Oct 7, 2012 #13
    -Well in that message, i meant "computer realtime".. that is a program that calculates simple dot speeds at realtime.... i dont mention "still dot" in that message..

    I understand what you say that Time is dependant on motion and gravity; and that is one of the reasons why i asked this questions on the original post too...

    What effect does all that speed have on us, or our perception of reality?.. what effect does it have in the physics we experience, in chemistry, in our perception of time, or in the effects of time in us, etc?..

    -For the little simulation i proposed tho, it wont be necesary to take in account those gravitational relativistic effects that will appear if we traveled thru the galaxy, or the universe..

    cause, it will be a simulation right? a mere graphical representation of the measured approximated centers of those objects (earth, sun, black hole in the middle of galaxy..) it is something so huge that is not going to change from our point of view...

    in other words, we're not travelling, our perception of time space and al it will change if we actually went out there to that places, but to simulate some simple dots in a computer you dont really need that...

    and in any case, those relativistic time dilation effects could also be included on that program, just as they are included on any GPS software, cause, its just numbers, any computer can do that..

    -Anyway, all that was a little mental excercise i imagined yesterday, when originally i was told that it would be pretty much impossible to know any speed at all, and that in the end everything sumed zero... it didnt seem too hard for a computer, if what wer're talking is about a simulation..

    And well all that was yesterday.. lol

    Today we have the amazing data that you did bring, and we're left with that big numbers!!
    Last edited: Oct 7, 2012
  15. Oct 7, 2012 #14


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    Jabbercookie you really need to read into relativity before trying to work these out. You are doing it wrong; motion is relative. There are reference frames where Earth is not moving and there are reference frames where we are moving at 0.99999...c. All are valid.

    There is no "objective motion". Your thought experiment doesn't make any sense because it seems to imply a privileged reference frame.
  16. Oct 7, 2012 #15
    Relative to what reference frame is the earth not moving?
  17. Oct 7, 2012 #16
    The earth.
  18. Oct 7, 2012 #17


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    The motion of the earth through space is complicated. Earth orbits the sun at about 20 km/s, the sun orbits the milky way at about 225 km/s, the milky way orbits the Virgo cluster at around 365 km/s, and the virgo cluster is hurdling toward the great attractor in Hydra at about 627 km/s relative to the rest frame of the CMB. The CMB rest frame is the reference frame preferred by scientists for characterizing the motion of galaxies through space.
  19. Oct 7, 2012 #18


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    A geosynchronous satellite, if you want something other than earth itself, and if you are willing to forget about rotational speed, then ANY satellite that is not changing altitude.
  20. Oct 7, 2012 #19
    This is still motion relative to something else. What we need now is the absolute motion of the CMBR.
  21. Oct 7, 2012 #20


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    Everyone has their own absolute frame from which they declare absolute motion. This is known as the egocentric frame.

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