Dark matter, the invisible substance thought to make up around 85 percent of all mass in the universe, forms an essential part of the standard cosmological model, providing the gravitational glue that holds together entire galaxies. What it actually is, though — and even if it truly exists — remains one of the great mysteries of science.
Now, a bizarre event that occurred nearly a mile underground at the world’s largest dark matter detector in South Dakota, the LZ detector, could be the first direct evidence of the substance. Or it could be something else entirely. Either way, it has scientists mystified and excited.
In a new paper published Tuesday and has been submitted to the journal Physical Review Letters, physicists running the LZ Dark Matter Experiment say that their detector recorded a stunning subatomic interaction that doesn’t fit anything else ever documented in physics.
Again, it’s not necessarily a dark matter discovery — but it’s so unusual that it warranted sharing.

