Look under your feet: the iron core of the earth. Many planets are supposed to have iron core. May be the sun have an iron core.
Droplet, vapor of an ancient supernova.
In the sky: white dwarf supernova remanent.
Triple system can eject one component.
Escape velocity of the galaxie < Ejected dwarf velocity
:->Intergalactic space.
Estimates of the population may vary widely with model of universe. One model may estimate that the net flow is toward the center and other that the galaxy is evaporating...
Observation hard to detect: dim, small and far...
What kind of effects do you expect? Magnetic conduction betwen galaxies. Maggnetic acceleration? Plasma