[VaRepublican]

I have a question. We have been studying galaxy movement for what, about a hundred years? ok maybe more. how do we know they are moving and how do these folks know how much they have moved?

[cripplecreek]

Just turned on the TV and there’s a show just starting on the Science Channel about exactly that.

A lot of it has to do with doppler shift and comparison with where things were in relation to us with where they are now.

I’m not fully awake yet so A can’t put things together too well.

[muir_redwoods]

The degree to which the have moved is based upon their red shift. The red shift is a phenomenon first observed by astronomer Edwin Hubble. This link explains it pretty well.

http://en.m.wikipedia.org/wiki/Edwin_Hubble

[Prospero]

Doppler shift, primarily. But don't let them fool you into thinking they have more figured out than they really do. For most of my life the big debate centered on the expansion of the cosmos and was squarely based on the assumption that the mutual attraction of all this matter was slowing the speed of this expansion. The question that occupied innumerable seminars and retreats was whether the momentum of expansion, all of it set in motion by the Big Bang, was sufficient to overcome this mutual attraction, whether it would slow and eventually collapse.

No one dreamed, let alone speculated, that the methodical study of the doppler shifts of all this structure would show that this expansion was actually speeding up!

And I won't even begin to relate how recent nor how baffling the study of individual galactic rotation has turned out to be, how galaxies turned out to rotate more like solid objects, pointing toward the conclusion that much more of the cosmos is composed of dark rather than visible matter, the nature of which is entirely unknown.

The practitioners of "science" as a religion have much further to go than they dare dream.