Although dark matter makes up 85% of the total mass in the universe, it is difficult to detect directly. A new study proposes a unique way to search for dark matter particles flying through the air, such as meteorites, by using Earth’s atmosphere as a giant detector. Dark matter is believed to permeate the cosmos and currently surrounds us all. So why can’t we find it? Because it is invisible – it does not emit, absorb or reflect light and very rarely interacts with ordinary matter. This may seem like a very convenient explanation, but scientists are pretty sure that dark matter exists.

While never experimentally confirmed, dark matter seems to make itself felt by its gravitational influence on stars, galaxies and clusters. The discovery of dark matter will be one of the most important scientific discoveries of all time, so it’s no wonder it’s the subject of many experiments.

One problem is that dark matter has a wide variety of potential properties, including different masses, energies, and interactions. That’s why physicists investigate dark matter by designing a series of different experiments that look for signals based on certain properties it may or may not have.

A new study led by Ohio State University researchers takes a unique approach. The team hypothesizes that if dark matter particles have a large mass, they can sometimes enter Earth’s atmosphere as meteorites, potentially leaving visible traces.

As meteors fly across the sky, they leave emission tails that produce free electrons. These “ionization deposits” reflect electromagnetic waves emitted by radar devices, allowing them to detect meteors passing through the air. The research team says dark matter particles will produce similar but different signals.

The researchers described what these dark matter meteorites might look like, and suggested that careful analysis of these radar signals could reveal whether they were all meteors or whether some were actually dark matter particles hiding in front of the eye. This effectively turns the entire atmosphere of the planet into a giant dark matter detector.

One of the key features of the proposed new method is that it will look for a type of dark matter that is often overlooked. Dark matter particles can be very light and ubiquitous, or have a very large mass and be relatively rare. Most experiments look for the former in large rooms deep in the ground, usually free of background noise. But if the particles are larger, they may not reach these detectors, which could explain the lack of positive results for decades. Thus, the new technique can expand the search and be used by other experiments to cross-check potential detections they may find.