Well, this is interesting… Just when cosmologists were starting to arrive at a consensus about the reality of Dark Matter and a sense of how it drives cosmic evolution, observations of Abell 520 completely contradict what people expect. The Dark Matter seems to be having no gravitation effect on galactic trajectories at all.

“”We were not expecting this,” the study team’s senior theorist, Arif Babul of the University of Victoria, said in a news release. “According to our current theory, galaxies and dark matter are expected to stay together, even through a collision. But that’s not what’s happening in Abell 520. Here, the dark matter appears to have pooled to form the dark core, but most of the associated galaxies seem to have moved on.”

[…]The results contradict what scientists thought they knew about dark matter. In a previous study of the Bullet Cluster, 3 billion light-years from Earth, astronomers found that concentrations of dark matter blasted through the scene of a collision, with their associated galaxies tagging along. Meanwhile, waves of hot, X-ray-emitting gas clumped up in the middle.

In the case of Abell 520, the situation is completely different: The galaxies sailed through the collision, but the dark matter piled up in the middle, along with the hot gas.

Researchers were hoping that Hubble would resolve the mystery first posed by the detection of the dark core in 2007. No such luck.”

More here.

Just another reminder that theologians need to be a little cautious before embracing a working hypothesis and turning it into a mechanism for doctrine. Heh. (And here I was starting to speculate on Dark Matter as the unseen heavenly reality that permeates all of the Cosmos.)