Not sure what you're asking. It doesn't contradict. There's schmutz (mostly remnants of exploded stars) between us and Sgr A and almost all visible light hits something before getting to us. Really long wavelengths might make it through, so the imaging that has been done was via these super-IR wavelengths.Greta wrote:How does the fact that light from the Sag A* area doesn't make it to us contradict your comment about light in intergalactic space.
Said schmutz is far less prevalent looking outward, so there seems to be no limit to our sight distance.
I'm saying that the physicists do not corroborate that belief. Red shift a difference between the frame of the observer and the frame of the emitting object, not a change to the photon.I expect that if a photon made it to intergalactic space - and most of that would come from stars around the galaxy's periphery - then maybe it might not ever encounter something, although I believe that over extremely long time periods (ie. even longer than the Stelliferous Era) it would lose heat and redshift ever more until it dissipated entirely.
If you observe a photon that originated from 10BLY away in the same frame as the object that emitted it, it would have the same frequency/energy as if you were there and had observed the thing shortly after it was emitted.
Similarly, you could be near the emitting object but choose to observe in the frame of our solar system now, and the photon would be fully red shifted.
If red shift was due to dissipation over distance, even light from Andromeda would be red shifted, not blue shifted. Is it picking up energy along the way? The blue shift is because we're moving toward Andromeda, a positive difference in frames instead of the usual negative one.