All of the other galaxies shown, are either being swallowed by it or are hidden by it. They were revealed using the CSIRO's Parkes radio telescope by non-visible radio imaging, by the University of Western Australia's ICRAR (International Center for Radio Astronomy Research) program and lie in a region of space known to astronomers, as, the "Zone of Avoidance" (well, yeah, for obvious reasons!).
|Artist's computer-generated image of the Milky Way Galaxy|
On an even more interesting note: all of these galaxies - ours included - are being 'pulled' by a gravitational anomaly known as, the "Great Attractor", into - well, whatever the Great Attractor is!
The Milky Way galaxy, itself, was not formed by standard galaxy formation theory; rather, it is an aggregation of interacting (no one is yet sure how many), formerly individual galaxies.