The Milky Way Galaxy resembles a distorted disk in two ways. The center is twisted, creating a kind of vortex. But from the side, “our galaxy looks like a small wave.”
This shape was recently discovered using the Gaia Space Telescope. It was launched in 2013 with the aim of accurately determining the position and speed of stars in the Milky Way Galaxy.
The reason for the shape of the galaxy was not known for a long time. The main theory was that the Milky Way was (or is) influenced by another galaxy.
CfA scientists used data from Gaia to create a computer model of the Milky Way. They then experimented with simulations to see if the shape could be created in the model.
According to researchers, there is a circle of dark matter around the Milky Way Galaxy, which is a heavy matter that is very difficult to observe on Earth. This resulted in the exact shape of the galaxy in the simulation.
This circle, also called the halo, is not perpendicular to the Milky Way. The poles (on Earth they are the North and South Poles) have probably rotated by about 25 degrees.
The halo is likely also affected by other galaxies. According to simulations, this would have happened about 7 billion years ago. This reduced the rotation of the corona.
