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Re: How galaxies make their rotation curves flat and what about dark matter?

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On 7/20/2021 12:24 PM, Paul Alsing wrote:
> On Monday, July 19, 2021 at 11:52:02 PM UTC-7, Michael Moroney wrote:
>> On 7/20/2021 12:42 AM, Paul Alsing wrote:
>>> On Monday, July 19, 2021 at 9:37:33 PM UTC-7, mitchr...@gmail.com wrote:
>>>
>>>> Galaxies don't rotate. Their stars orbit the gravitational center.
>>>
>>> That is pretty much the same thing, Mitch...
> 
>> Is it? Galaxies don't rotate as a unit like a record on a record player.
>> They're more like a hurricane, with the center rotating more rapidly
>> than outer stars. Or even the solar system with inner planets orbiting
>> much more rapidly than outer planets. Do you say the solar system rotate?
> 
> I agree, like a hurricane, rotating more rapidly in the center... you did use the word 'rotating", Mike, didn't you? I use it exactly the same way as you use it. Regarding the solar system, I never gave that a thought. Planets and other solar system bodies rotate around their axes, of course, but are more correctly 'revolving' around the Sun. If you were to say that galaxies revolve rather than rotate, I could not argue with that claim, but the literature all seems to use the term 'rotate' for some reason. I don't know that it really makes much difference, as long we all agree as to what it means.
> 
> https://tinyurl.com/2v75bt3h
> 
> When Mitch claims that galaxies do not rotate, he is incorrect as far as the scientific community is concerned. When he says that the stars of a galaxy orbit the gravitational center, he is correct.

Apparently Mitch missed the lecture where the discussion
centered on "the whole is the sum of its parts."

Not to be confused with a systems analysis in which
the system is larger than the sum of its parts.

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Re: How galaxies make their rotation curves flat and what about dark matter? PengKuan Em <titang78@gmail.com> - 2021-07-19 15:16 -0700
  Re: How galaxies make their rotation curves flat and what about dark matter? "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2021-07-19 21:37 -0700
    Re: How galaxies make their rotation curves flat and what about dark matter? Paul Alsing <pnalsing@gmail.com> - 2021-07-19 21:42 -0700
      Re: How galaxies make their rotation curves flat and what about dark matter? Michael Moroney <moroney@world.std.spaamtrap.com> - 2021-07-20 02:51 -0400
        Re: How galaxies make their rotation curves flat and what about dark matter? Clutterfreak <clutterfreakincarnate@gmail.com> - 2021-07-20 11:56 -0500
          Re: How galaxies make their rotation curves flat and what about dark matter? Paul Alsing <pnalsing@gmail.com> - 2021-07-20 10:33 -0700
            Re: How galaxies make their rotation curves flat and what about dark matter? Clutterfreak <clutterfreakincarnate@gmail.com> - 2021-07-20 13:40 -0500
              Re: How galaxies make their rotation curves flat and what about dark matter? "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2021-07-20 12:08 -0700
              Re: How galaxies make their rotation curves flat and what about dark matter? Paul Alsing <pnalsing@gmail.com> - 2021-07-20 13:08 -0700
                Re: How galaxies make their rotation curves flat and what about dark matter? "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2021-07-20 18:21 -0700
        Re: How galaxies make their rotation curves flat and what about dark matter? Paul Alsing <pnalsing@gmail.com> - 2021-07-20 10:24 -0700
          Re: How galaxies make their rotation curves flat and what about dark matter? whodat <whodaat@void.nowgre.com> - 2021-07-20 22:11 -0500
        Re: How galaxies make their rotation curves flat and what about dark matter? PengKuan Em <titang78@gmail.com> - 2021-07-22 18:42 -0700
      Re: How galaxies make their rotation curves flat and what about dark matter? "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2021-07-20 10:57 -0700

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