Galaxy’s missing matter can be found – but now there’s too much

Many large galaxies have long been thought to lack a huge proportion of matter – but this has now been discovered, and it’s an even bigger problem for our understanding of the universe.

Observations over the past decade have shown that galaxies the size of the Milky Way seem to have far less baryonic matter — that is, normal matter, not dark matter — than we thought. This expectation is based on the ratio of dark matter to regular matter…