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Andromeda Devouring Neighbor Galaxy
Scientific Ninja writes "Astronomers in the University of Sydney have captured pictures of a 'union' between our closest neighboring galaxy, Andromeda, and its smaller neighbor, the Triangulum Galaxy. Published in the journal Nature on September 3rd, the research shows how large galaxies grow by incorporating stars from surrounding smaller galaxies. This popular model of galaxy evolution, called the 'hierarchical model,' predicts that large galaxies such as Andromeda, which can be seen with the naked eye from the northern hemisphere, should be surrounded by relics of smaller galaxies it has connected with."
This is local. What's happening on a global (ok, universal) scale is that the universe is expanding and after 100 trillion years all the hydrogen will be used up and there will be no more stars (or at least very few of them) and 10^whatever years after that the universe will just be a bunch of black holes slowly oozing out Hawking radiation. Very bleak.
So says the species that still thinks there is "Dark matter" and "dark energy" out there somewhere.
Physicists don't like to dwell on this point when summarizing what their research accomplished, but we really don't know enough to be definitive about how the universe will evolve. To wit: our LOCAL time-cone appears to be expanding, and if (1) this observation is correct, (2) the universe is homogenous to our time-cone, and (3) there isn't some exterior force pushing us together, then we'll all wind up in a cold death in the end.
For all we know, the vacuum of space might just have a slight red-tint to it, causing this "red-shift" that makes us think the universe is expanding. It's not like we have rulers or anything.