The universe is all about improv and showing there can be more than one way to get to the same result. While I am comfortable with the idea that those blue blobs will become dwarf galaxies, that isn’t to say there may not be other ways to make these systems.
Here is what we know so far: Dwarf galaxies typically have one or a few generations of star formation and then die, but there are exceptions. They are typically very old, but occasionally we find young ones. They are generally spread evenly around large galaxies, in numbers that are proportional to the primary galaxy’s size, but that too has exceptions.
Case in point. In a presentation at last week’s American Astronomical Society (AAS) meeting, researchers led by Eric Bell presented an image of the galaxy group dominated by the spiral galaxy M81. In this system, they found one certain and six potential dwarf galaxies all hanging out on one side of M81. Now, it is possible there is only one dwarf, and it picked a side to be on. But if those possible dwarfs are dwarfs, this is just a statistically weird system.
There are no rules – except the speed of light. Expect everything.
More Information
University of Michigan press release
Seven newfound dwarf galaxies sit on just one side of a larger galaxy (Science News)
