Gravitational lensing effects in this Hubble capture of Abell 1689 indicates the presence of dark matter.
Dark matter is mysterious matter that we can’t see but is thought to comprise a large amount of our universe. Even though we can’t see it, a group of scientist now estimate that a dark matter particle bumps into us once every minute. From Popular Science:
We know dark matter does not interact normally with regular matter — otherwise we’d be able to see it — so that means most of the particles pass through us. But some might interact with a hydrogen or oxygen nucleus, changing their energies or spins. The researchers use a 70-kg human (about 155 pounds) as an example, and calculate how many particles may be careening around based on signals from the DAMA, CoGeNT and CRESST experiments. Of the billions of high-energy WIMPs passing through a body every second, fewer than 10 hit a body’s nuclei in a given year. But lower energy WIMPs make impact much more frequently, around 100,000 collisions per person per year. That’s about one per minute.
What does this mean? Maybe nothing, in terms of impacts on human health — cosmic and solar radiation also rains down on us all the time, and it has many more detrimental effects. But it’s interesting to think that we ourselves could be dark matter detectors.
More details here.