In a significant discovery, the long-suspected electric field around Earth has been seen to generate a kind of polar wind that carries particles through space at supersonic speeds. Scientists call it the “ambipolar electric field,” a weak phenomenon on a global scale — first theorized more than 60 years ago. The recent observations, from NASA’s Endurance rocket, were published in Natureconfirm its existence and suggest that it significantly affects the Earth’s atmosphere, particularly at the poles.
According to NASA, the ambipolar electric field is a major driver of the “polar wind,” a steady flow of charged particles in space above Earth’s poles. This electric field lifts charged particles to higher altitudes in our upper atmosphere than they would otherwise reach and may have shaped our planet’s evolution in ways yet to be explored.
Measurements from NASA’s Endurance mission rocket have confirmed the existence of the ambipolar field and quantified its strength, revealing its role in driving atmospheric escape and shaping our ionosphere — a layer of the upper atmosphere — more broadly.
Understanding the complex activities and evolution of our planet’s atmosphere not only provides clues about Earth’s history, but also gives us insight into the mysteries of other planets and helps determine which planets may be favorable for life. The research paper was published in the journal Nature on Wednesday, August 28, 2024.
“Something must be pulling these particles out of the atmosphere,” said Glynn Collinson, Endurance’s principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the paper’s lead author. Scientists suspect a not-yet-discovered electric field may be at work.
“It’s like a conveyor belt, lifting the atmosphere up into space,” Collinson said.
Endurance’s discovery opens up many new avenues for exploration. As our planet’s fundamental energy field, along with gravity and magnetism, the ambipolar field has continually shaped the evolution of our atmosphere, which we can now begin to explore. Because it is produced by the internal dynamics of the atmosphere, similar electric fields are expected to exist on other planets, including Venus and Mars.
“Any planet with an atmosphere should have a bipolar region,” Collinson said. “Now that we’ve measured it, we can start to learn how it has shaped our planet, as well as other planets, over time.”
