text: how do irregular galaxies effect the earth or outer space? or anything else about galaxies technically, anything with mass has gravity and there is no limit to gravity's range, but the affect on the earth is astronomically (pardon the pun) small and may be beyond our ability to detect. that being said, there is another thing that massive object can do, and that is that they can act as a "gravitational lens".  we may be able to "see" another galaxy or object that is behind the irregular galaxy simple because the mass of the galaxy bends space to the point that the light from the other object bends around it and we can then see it.  this phenomenon has been observed on a small scale, and its effect can be caused by any massive object, not just an irregular galaxy.