vesto slipher was the first to notice that distant galaxies were red shifted with respect to closer stars.
vesto slipher was the first to notice that distant galaxies were red shifted with respect to closer stars.
who was the first to notice that distant galaxies were red shifted with respect to closer stars?
vesto slipher
Na
Na
assuming that dark energy continues to make the universe expand at an accelerating rate, in about 150 billion years all galaxies outside the local supercluster will pass behind the cosmological horizon. it will then be impossible for events in the local group to affect other galaxies. similarly it will be impossible for events after 150 billion years, as seen by observers in distant galaxies, to affect events in the local group. however, an observer in the local supercluster will continue to see distant galaxies, but events they observe will become exponentially more red shifted as the galaxy approaches the horizon until time in the distant galaxy seems to stop. the observer in the local supercluster never observes events after 150 billion years in their local time, and eventually all light and background radiation lying outside the local supercluster will appear to blink out as light becomes so redshifted that its wavelength has become longer than the physical diameter of the horizon.
future of an expanding universe