Question

what is the between milky Way and Andromeda
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Answer 1

Answer:

The Andromeda–Milky Waycollision is a galactic collision predicted to occur in about 4.5 billion years between two galaxies in the Local Group—theMilky Way (which contains the Solar System and Earth) and theAndromeda Galaxy. ... Some stars will be ejected from the resulting galaxy, nicknamed Milkomeda or Milkdromeda.

Answer 2

Answer: Dark Matter

Explanation : The space between galaxies is "mostly" empty, but the distribution is far from uniform. Astronomers have abundant gravitational evidence that an unseen component, which we simply call "dark matter", surrounds all large galaxies and clusters of  galaxies.