Question: Have we found more dark matter than fairies all this time?
The issues at stake are huge. Acceptance of dark matter has influenced scientific thinking about the birth of the Universe, the evolution of galaxies and black holes, and the fundamental laws of physics. Yet even within academic circles, there is a lot of confusion about dark matter, with evidence and interpretation often conflated in misleading and unproductive ways …
This is how I stumbled into the field in the late 1990s. I was studying the dynamics of small satellite galaxies as they orbit our galaxy, the Milky Way. From observation, we expected that these satellite galaxies must contain a lot of dark matter, from 10 to 1,000 times as much as their visible, normal matter. During my calculations, I made a perplexing discovery. My simulations produced satellite galaxies that look much like the ones actually observed, but they contained no dark matter. It seemed that observers had made wrong assumptions about the way the stars move within the satellite galaxies; dark matter was not required to explain their structures.
Pavel Kroupa, “Has dogma derailed the scientific search for dark matter?” at Aeon
It’s a lot like Darwinian evolution except that, in this case, people are willing to talk about it.
See also: Are dark matter and dark energy scientific?