See where musicians are located in the Music Galaxy based on the overlap of their listeners. The greater the overlap between audiences, the closer the musicians/bands will be located in the galaxy. For example, a lot of people who listen to The Beatles also listen to The Beach Boys, so those two bands are close in proximity on the map. You can browse around the galaxy with your trackpad, or you can search for an artist and "fly" to them on the map.
From Music Galaxy: "This is a visualization of the relationships and audience listening patterns of over 70,000 music groups + artists. Artists are placed nearby other artists with similar listeners."