A new study suggests that Earth's upper atmosphere could contain a missing piece of the universe

The Earth may be swimming in an ocean of Dark matter – And waves in this invisible ocean crashing into the upper layer of our planet’s atmosphere may generate detectable radio waves that allow us to finally find this elusive component of the universe, according to new theoretical research.

A large body of astrophysical and cosmological evidence points to the existence of dark matter, from the inexplicable rotation curves of some galaxies, to the growth of the largest structures in the universe. Attempts to explain this wide variety of observations with alternative formulas to gravity It failed, so the vast majority of astronomers believe that dark matter is an unknown form of matter that rarely interacts with light or with ordinary matter.

But this is a very broad idea that includes a lot of possibilities. Dark matter They can be made of huge moleculesBut searches for this type of particle have been largely empty. So an interesting alternative is that dark matter is exceptionally light, either in the form of theoretical particles known as axions or as an exotic form of photon that carries very little mass.

With that incredible lightness – millions of times lighter than the lightest known particles – dark matter can behave in very strange ways. In particular, instead of appearing as individual bullets, dark matter will appear They act like big waves that revolves around the universe.

in Recent study Published on the preprint server arXiv, physicists explored models of ultralight dark matter that were not completely dark, allowing them to interact extremely rarely with ordinary matter. Most of the time, these interactions are barely recorded, and do not produce anything detectable. But on rare occasions, dark matter and normal matter have interacted enough to produce a significant amount of… radio waves.

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This will happen when dark matter encounters A plasma When the frequency of dark matter waves lines up with the frequency of plasma waves. When that happens, a resonance will occur, amplifying the interaction and producing radiation in the form of radio waves, the team’s models suggested.

The universe is no stranger to plasma. All stars spew plasma into space in the form of stellar winds, so scientists have already discovered the production of radio waves due to the interaction of dark matter with environments such as the solar corona or the interstellar medium. But in this new research, scientists have discovered a point of interaction much closer to Earth: our planet’s ionosphere.

The Earth’s ionosphere is the thin, hot layer of the upper atmosphere, consisting of a loose collection of ionized (charged) particles – plasma. It is natural for waves to pass through it, and researchers discovered that those waves could interact with waves of hypothetical dark matter that might engulf the Earth.

The radio waves generated by this interaction would be difficult to detect. But the researchers found that by using a radio antenna carefully tuned to search for a specific frequency of radio waves over the course of a year, they might be able to detect these waves.

This idea is particularly promising because the Earth’s ionosphere offers several advantages over other sources of radio waves generated by dark matter. First, the ionosphere naturally reflects many radio waves from deeper space, making it relatively free of contaminated signals. Second, the ionosphere is located directly above us, is easily accessible, and is already the subject of constant observation and study.

It’s a long shot. This form of dark matter is highly theoretical, and it will take years, if not decades, to perfect the observational technology to search for these radio waves. But if it works, it will be a goldmine, allowing us to study one of the universe’s most mysterious elements right on our cosmic doorstep.