Intergalactic travel is space travel between galaxies. Due to the enormous distances between our own galaxy the Milky Way and even its closest neighbors
The technology required to travel between galaxies is far beyond humanity’s present capabilities, and currently only the subject of speculation, hypothesis, and science fiction.
However, scientifically speaking, there is nothing to indicate that intergalactic travel is impossible. There are in fact several conceivable methods of doing it; to date there have been a few people who have studied intergalactic travel in a serious manner.[1][2][3][4]
The difficulties of intergalactic travel
Colossal distances
Due to the size of the distances involved any serious attempt to travel between galaxies would require methods of propulsion far beyond what is currently thought possible in order to bring a large craft close to the speed of light.
Speed of light limit
According to the current understanding of physics, an object within space-time cannot exceed the speed of light,[5] which condemns any attempt to travel to other galaxies to a journey of millions of earth years via traditional standards.
Another difficulty would be to navigate the spacecraft to the target galaxy and succeed in reaching a chosen star, planet or other body, as this would require a full understanding of the movement of galaxies which has not yet been attained.
Communication and one-way trip
There is also the considerable problem, even for unmanned probes, that any communication between the craft and its home planet can still only travel at the speed of light, which may require millions of years to traverse the colossal distances involved. Even if another galaxy could be reached, there seems to be no way for the information to be transmitted home in any meaningful way. The only possible fast way of communication would be faster-than-light communication, such as communication through a transversable wormhole.