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Author Topic: The Moon orbits Earth, the Earth the Sun, Sun the Milky way...The Universe?  (Read 2983 times)

Offline acecharly

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any ideas?

Cheers

Ace


 

Offline imatfaal

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The milky way orbits the centre of mass of the local group of galaxies (I think)
 

Offline Soul Surfer

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Yes it will. but the problem with "orbits" on the scale of galaxy clusters is that they take a significant fraction of the time since the big bang to be completed and conditions change radically during the period of the orbit.
 

Offline CliffordK

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Obviously one wouldn't need a complete circle to determine a circular orbit.  However, one would expect generally clockwise or counterclockwise motion.

The portion of the universe we can see from Earth seems to be very much space filling, rather than planar like our solar system and most galaxies.  I believe, however, the motions of different galaxies is somewhat chaotic with some approaching us, some receding from us, so there doesn't appear to be coherent orbiting.  There still could be some alterations of directions of motion due to a universe center of gravity without fully developed coherent motion.
 

Offline imatfaal

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Hi Cliff - what I was getting at, and Surfer is correct to mention the silly orbtal times, is that we are not gravitationally bound to the vast majority of the universe.  It is nearly all leaving us, but the local group is gravitationally bound.  We are close enough that gravity is strong enough to keep us together for the foreseeable future - we can presume (it has probably be proved - but I dunno)  that there will be some ang mom, so therefore we will be in orbit around the c of m.

Surfer - from my reading the local group will stay bound as long as they exist, it will end up with us, Andromeda, and 50 or so others lost and alone cut off from the rest of the universe.  I dont think we will even hang onto the rest of the virgo supercluster.  Whilst we wont be there to watch I think we will properly orbit before the heat death
 

Offline Ęthelwulf

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The milky way orbits the centre of mass of the local group of galaxies (I think)

Galaxies like our own, orbit in large stuctures for what are called, supergalaxies.

Supergalaxies are many galaxies mixed in rotation together.
 

Offline Bill S

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Interesting that no one addressed the last part of the OP.   

  In an article in New Scientist, Marcus Chown (10.06.2006. Pp. 34-37) looks at the work of Pawel Mazur, George Chapline and others who think it is quite possible that the entire cosmos is “spinning on an axis”.   So their work might be a good place to start.
 

Offline acecharly

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Interesting that no one addressed the last part of the OP.   

  In an article in New Scientist, Marcus Chown (10.06.2006. Pp. 34-37) looks at the work of Pawel Mazur, George Chapline and others who think it is quite possible that the entire cosmos is “spinning on an axis”.   So their work might be a good place to start.


It would makes sense that the universe was rotating on an axis this could make galaxies spin just like hurricanes spin due to the spin of the Earth maybe
 

Offline Airthumbs

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If the Universe was rotating on an axis it should be slowing down due to the expansion........  how would you measure something like that??
 

Offline syhprum

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I do get fed up with references to the universe rotating!, by definition the universe is all there is so relative to what does it rotate ?.
 

Offline acecharly

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Its all there is that we know about at the moment one day we may find something beyond this shell we call the universe its more acceptable an idea than there being nothing surely. By definition the universe may be everything its also a manmade word like all others and does not mean its definition is correct.
« Last Edit: 08/04/2012 18:50:51 by acecharly »
 

Offline Airthumbs

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I do get fed up with references to the universe rotating!, by definition the universe is all there is so relative to what does it rotate ?.

I thought by definition the Universe is all we know.  One time the Universe was the Milky Way yes? Before that the Solar System and before that Earth!

Have we become so confident and advanced as our predecessors believed that we can state that what we see is all there is?
 

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