As early as the 1930s, Swiss astronomer Fritz Zwicky noticed that galaxies in the Coma Cluster were moving far too fast to be held together by visible matter alone. He coined the term "dunkle Materie" (dark matter) to describe the missing mass. Gravitational Lensing
Most evidence suggests dark matter is "cold," meaning its particles move slowly relative to the speed of light. 🔭 Key Evidence Dark Matter
The exact identity of dark matter remains unknown, though several leading theories exist: The quest for dark matter with Matt Bothwell As early as the 1930s, Swiss astronomer Fritz
It provides the "glue" that keeps galaxies from flying apart. 🔭 Key Evidence The exact identity of dark
In the 1970s, astronomer Vera Rubin observed that stars at the edges of spiral galaxies were moving just as fast as those near the center. According to Newtonian physics, they should have been moving much slower or flying off into space unless some unseen mass was holding them in place. Galaxy Clusters
Scientists discovered dark matter not by seeing it, but by noticing that the universe's "math" didn't add up without it. Galaxy Rotation Curves