Scientists searching for dark matter have detected an unusual particle event that could be a sign of the mysterious substance, according to the international LUX-ZEPLIN (LZ) collaboration.
The event was detected by LZ, a large detector located nearly 1.5 kilometers underground in South Dakota, United States. Researchers analyzed 220 live days of data collected between March 2023 and April 2024 and found one event that stood out from the signals they normally expect to see.
The experiment is designed to detect tiny signals that could occur when a dark matter particle hits an atom. In the new data, researchers found one such signal. It drew their attention because it appeared in a part of the detector where they expected very few signals from other known sources.
However, one event is not enough to prove that dark matter caused it. Scientists still need to determine whether it could have come from another rare process.
“With only one event, we don’t want to get ahead of ourselves. We are not claiming to have seen dark matter. But we have seen something interesting that we want to share with the scientific community for their input,” said Rick Gaitskell, spokesperson for the LZ collaboration.
The findings were presented on September 1, 2026, at the TeV Particle Astrophysics conference in Japan. The study was also released as a preprint on arXiv and submitted to Physical Review Letters for peer review.
What scientists know about dark matter
Dark matter is the name scientists give to an unseen form of matter that could explain gravitational effects observed across the universe. It is estimated to account for about 85% of all matter.
Scientists cannot see this proposed matter directly because it does not appear to interact with light in the way ordinary matter does. Instead, they observe gravitational effects that cannot be fully explained by the matter they can see.
For example, scientists have observed that stars at the outer edges of galaxies move much faster than they should if the galaxies contained only the matter we can see. At those speeds, the stars should eventually escape the galaxies instead of remaining in orbit around them. This suggests that there is additional mass creating extra gravity that cannot be seen directly. Scientists call this proposed unseen matter “dark matter.”
But scientists still do not know what dark matter actually is. Several hypotheses have been proposed, including WIMPs (hypothetical heavy particles that would interact very weakly with ordinary matter) and axions (hypothetical extremely light particles), as well as primordial black holes (black holes that may have formed in the early universe). None of these explanations has yet been confirmed.
In other words, scientists have strong evidence for unexplained gravitational effects, but the true nature of what is causing them remains one of the biggest questions in modern physics.
A confirmed detection would allow scientists to study that missing piece directly for the first time. It could help explain how galaxies formed, how the universe developed and what the universe is fundamentally made of.
