First stellar stream beyond the Milky Way could reveal dark matter

A faint ribbon of stars can be seen stretching across the galaxy in the image above. Known as a globular cluster stellar stream, this type of structure preserves clues about its past motion and evolution. By studying these streams, astronomers can learn more about how galaxies developed and how dark matter is distributed within them.

Because these stellar streams respond to gravity, they can act as tracers of dark matter that cannot be seen directly. Until recently, their extreme faintness made them very difficult to detect and analyze. Improvements in massive astronomical datasets and advanced analysis methods are now turning stellar streams into one of the most promising tools for studying galaxies.

First Stellar Stream Found Beyond the Milky Way