Third time's the charm for a row of faint galaxies without dark matter
2 days ago
- #galaxy formation
- #astronomy
- #dark matter
- A third dwarf galaxy, NGC 1052-DF9, 67 million light-years away, has been found to lack dark matter, joining DF2 and DF4.
- These three galaxies form a linear alignment with others, suggesting they originated from an extreme event like a high-speed galactic collision.
- Analysis using the Keck Observatory's Cosmic Web Imager revealed DF9's mass matches visible matter only, with no dark matter present.
- The discovery challenges the prevailing theory that galaxies form within dark matter halos, indicating dark matter is a distinct substance separable from normal matter.
- Follow-up observations with telescopes like Mothra aim to trace leftover gas from the collision, offering new insights into dark matter's nature.