The following video is a computer simulation that depicts the evolution of a galaxy. It’s based off our own Milky Way, and begins from the Big Bang to the the present, spanning a period of 13 billion of years (give or take a few billion, since we don’t know for sure). It comes from the science blog Starts with a Bang.
The video is credited to Fabio Governato et al, the University of Washington, and NASA Advanced Supercomputing. The caption reads:
Mergers of galaxies are common in their evolution. This movie shows the evolution of a galaxy with similar mass to our own Milky Way, commencing shortly after the Big Bang. The simulation is in a fully cosmological setting, according to our knowledge of Big Bang cosmology. This particular galaxy has a rich merging history, including a major merger at redshift of ~1, i.e. at a time when the Universe was almost half its current age. A large disk reforms from gas left over after the merger, and from subsequent gaseous accretion.
On another note, the creator of Starts with a Bang, Ethan Siegel, is using this video to bring attention to an interesting project, The Charity Engine; basically, you can contribute your computer’s time and processing power to help with scientific calculations like those involved in this simulation, while also giving to charities at the same time. It’s a worthy cause to look into, especially if you want more videos like this.
It’s amazing to imagine that this sort of thing is happening all over the universe, at this very moment. It’s on a scale of time, size, and power that is literally incomprehensible to our own minds and lifespans. It’s breathtaking how small we are in this universe.
Hat tip to Jerry Coyne of Why Evolution is True for raising this to my attention.