Recently reported that a research team at Gran Sasso National Laboratory in Italy have observed “ghost particles” called geoneutrinos that are coming from the center of the Earth — but what are they, and what do they do? The truth is pretty fascinating.

The scientists recorded a total of 24 geoneutrinos, and these “ghost particles” are so called because they are incredibly tiny, with 500,000 times less mass than an electron, making it extremely difficult to observe.

Chances are, you haven’t heard of them. After all, this study is one of the first to even observe them in any meaningful way. But as it turns out, they could have a huge effect on our understanding of the Earth.

Geoneutrinos are more formally known as electron antineutrinos that are basically decaying subatomic particles that occur naturally in the Earth from nuclear reactions, and therefore observing them helps scientists understand how much heat is being created by radioactivity deep under the crust of the Earth. Measuring these “ghost particles” allows scientists to put real figures on just how much energy is being produced by this radioactivity.

Because geoneutrinos are so small, matter is virtually transparent to them and so they speed through everything in its past at near light speed through the Earth, carrying their radioactive energy out into space and passing everything else by as it speeds through our planet.

Very occasionally, one of these geoneutrinos will collide with an atom, creating a flash of light and allowing scientists to catch a glimpse of them, if only for a fleeting moment. It’s the only way to view them so far. Scientists at the laboratory used a sphere of special oil and hundreds of sensors over a long period of time just to catch a handful of glimpses of this elusive piece of matter — 24 in all, with 11 coming from deep within the Earth.

It could completely change scientists’ understanding of the incredible energy being generated deep below our feet.