I know some galaxy orbite around other galaxy but are they orbiting only around each other?
well i just found this thread.
i will search next time before posting a new thread...
Yes, what else would they orbit?
Galaxies can be seen orbiting each other 'too quickly' to be explained by the matter the systems contain, another strong statement for the existence of dark matter. Hydrogen and helium gas has been detected/imaged with radio (X-ray?) telescopes in the center of the orbits at density and temperature being explained by the gravitation of the dark matter.
Want to cite source - believe it was during UC Irvine video lecture on Expanding Universe - James Bullock
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