Plasma comprises 99.999% of the cosmos. Researchers modeled the radio chirps of this subatomic slosh on Mars in a Nature Communications report released Tuesday.

Unusual Earth. We breathe a neutral gas film. However, hundreds of miles above the planet’s surface—roughly the distance between Paris and Amsterdam—problems arise. In the 1950s, before the Apollo missions, the deepest Van Allen radiation belt was identified. Two belts, possibly three.

These chirps help explain plasma and much of space. This mystery is formed millions of miles above Earth. Satellites and astronauts are at risk from plasma in the Van Allen radiation belts. It can impact Earthly life.

“Right now, more than anytime in history, humankind is becoming much much more connected to the space environment,” says article author, atmospheric scientist, and Space Institute founder Jacob Bortnik.

He thinks cellphones work by engaging with several satellites at once, and knowing the space environment will become almost as important as understanding terrestrial weather. These waves are intricate.

What’s plasma?

Plasma is charged gas. Earth’s electromagnetic field directs plasma into the donut-shaped Van Allen radiation belts, which safeguard ourselves and our loved ones from damaging cosmic radiation.

Plasma interacts with this force, and the whistle tones may reveal how it travels and changes the universe above our planet and beyond.

Xin Tao has contemplated these whistling tones for a decade. The Deep Space Exploration Laboratory at the University of Science and Technology of China employs plasma researcher and paper author Tao. He tested his chirp model in the new work. He intended to test his idea, which explained the chirps on Earth, on Mars.

“They sound like birds.”

Radio waves make these chirps. Bortnik thinks they sound like birds on a loudspeaker. Chorus waves emit them. “Once we realized they came from space, it was really hard to explain why they chirped the way they chirped,” Bortnik explains.

The team used Mars chorus emission data. This planet is magnetically neutral. Unlike Earth’s, it’s local. Scientists believe Mars’ liquid core formed one long ago. The magnetic field stopped when that metallic substance stopped moving.

Mars’ surface shows magnetic fields. Bortnik calls the dispersed fields “pasted to the crust.” Tao’s theory is tested in this unusual form.

Inverse reports that Martian fields circle up and down. Earth contains worldwide apple-half-shaped field lines that feed back into the globe at the poles, unlike this. It’s why high-latitude auroras exist. Plasma affects them.

What They Found

To understand plasma and why chorus waves “chirp,” scientists analyzed how electromagnetic waves affect plasma trajectory and electromagnetic waves.

The model proposes that plasma chirps due to background electromagnetic field “inhomogeneity.” Tao and Bortnik say the model works both Earth’s strong magnetosphere and Mars’ lesser magnetic fields.

Tao tells Inverse that once waves alter charged particles, they must send energy back to the waves.

Plasma particles form a space ring and bounce along the magnetic field. Radio waves indicate resonance and direction. Bortnik argues that if you bundle plasma particles together like an antenna and put them in a changing field that changes their travel speed, they radiate differently and generate a new frequency. The chirps finish.

The crew liked Tao’s model. To prove the concept applies to plasma across the Solar System, more investigation is needed.

Bortnik thinks this technology might be used for deep space propulsion when probes are too distant from the Sun to capture solar energy.

Space is thrilling and full of intellectual and practical challenges. Bortnik thinks it affects our daily life.