A universe that’s dominated by dark stuff used to seem preposterous to some of the scientists earlier but now we’ve closed this loophole about gravity, and we’ve come closer than ever to seeing this invisible matter.
Researchers at the University of California, Santa Cruz, have used NASA’s most powerful supercomputer to run the largest simulation to date of the formation and evolution of the dark matter halo that envelopes the Milky Way galaxy. These observations provide the strongest evidence yet that most of the matter in the universe is dark and provides a valuable tool for understanding the evolutionary history of our galaxy.
Every galaxy is surrounded by a halo of mysterious dark matter that can only be detected indirectly by observing its gravitational effects. The first small galaxies formed very early, about 500 million years after the Big Bang, and still today, there are stars in our galaxy that formed at this early time, like a fossil record of early star formation. The new research can provide the setting for where those old stars came from and how they ended up in dwarf galaxies and in certain orbits in the stellar halo today.
Although the nature of dark matter remains a mystery, it appears to account for about 82 percent of the matter in the universe. The most interesting part that comes out from the largest simulation is that there are big clumps of dark matter in the same region where the disk of the Milky Way would be. So even in the local neighborhood of our solar system, the distribution of dark matter may be more complicated than we have assumed.
The simulation will also provide a useful tool for observational astronomers studying the oldest stars in our galaxy by providing a link between current observations and earlier phases of galaxy formation.
Via: ucsc
