Dark matter makes up roughly , dwarfing the "ordinary" matter—stars, planets, and people—which accounts for less than 5%.
The exact identity of dark matter remains unknown, though several leading theories exist: The quest for dark matter with Matt Bothwell Dark Matter
It provides the "glue" that keeps galaxies from flying apart. Dark matter makes up roughly , dwarfing the
It does not interact with electromagnetic forces, meaning it is completely transparent. Dark matter makes up roughly
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