Mysterious galaxy without dark matter puzzles astronomers
The universe is expanding extremely fast. Every second, stars are sailing away from each other, galaxies are entering new cosmic territory, and oddly enough, it's happening way too quickly. Even the most elegant calculations suggest there isn't sufficient matter in space to account for the speedy movement. That's where dark matter comes in.
https://www.cnet.com/news/mysterious-galaxy-without-dark-matter-puzzles-astronomers