Dark Matter -

It provides the "glue" that keeps galaxies from flying apart.

The exact identity of dark matter remains unknown, though several leading theories exist: The quest for dark matter with Matt Bothwell Dark Matter

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 It provides the "glue" that keeps galaxies from flying apart

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 Galaxy Clusters Scientists discovered dark matter not by

Dark matter makes up roughly , dwarfing the "ordinary" matter—stars, planets, and people—which accounts for less than 5%.

Dark matter is one of the most significant mysteries in modern science, representing a substance that does not emit, absorb, or reflect light, yet exerts a powerful gravitational pull on the universe. While it remains invisible to traditional telescopes, its presence is inferred by its impact on the visible world. The Cosmic Invisible