May 19, 2017
We’ve created a ‘bubble’ around the Earth
The effects of human activity have long been cited as a primary cause of global climate change, but new research from NASA has revealed that our use of technology also appears to be having an impact not just on the planet, but on Earth’s near-space environment as well.
As the US space agency announced on Wednesday, the Van Allen space probes have detected a new, artificial bubble surrounding Earth that was the result of the interplay between very low frequency (VLF) radio communications and high-energy radiation particles.
In certain situations, these interactions can create a barrier surrounding the planet and protect it from solar flares, coronal mass ejections, and other potentially dangerous space weather, NASA said. A paper detailing the discovery has been published by the journal Space Science Reviews.
“A number of experiments and observations have figured out that, under the right conditions, radio communications signals in the VLF frequency range can in fact affect the properties of the high-energy radiation environment around the Earth,” explained Phil Erickson, assistant director at the MIT Haystack Observatory in Westford, Massachusetts.
NASA looking to use VLF waves to defend against space weather
As The Atlantic correctly pointed out, Earth already has its own, natural protective bubble – the magnetosphere, a region of space that surround the planet in which its magnetic field controls the charged particles found nearby. The new bubble, the publication noted, formed accidentally.
Humans use VLF waves when they want to communicate with submarines traveling at or near the surface of the ocean. These waves, which are emitted from ground-based stations, can travel to the Earth’s atmosphere and beyond. When they do, they can alter the movement of radiation particles in the vicinity, and on occasion, this interaction leads to the creation of a barrier which can be spotted by the orbiting Van Allen Probes.
The Van Allen Probes, NASA explained, study electrons and ions in the near-Earth environment. While completing their mission, the probes noticed that the outward extent of this newly created sphere stretches almost precisely to the inner edge of the Van Allen radiation belts (a layer made up of charged particles that is held in place by the planet’s magnetic fields).
The inner edge of the Van Allen belts is farther away from the Earth now than they were back in the 1960s, The Atlantic noted. Humans sent fewer VLF transmissions back then, leading NASA scientists to speculate that if the low-frequency waves were not around, then the Van Allen belts would likely be much closer to the surface of the planet than they currently are.
With additional research, Erickson and his colleagues believe that VLF transmissions could be a way to remove excess amounts of radiation from the near-Earth environment. The agency is now planning to test VLF transmissions in the upper atmosphere to determine whether or not they can successfully remove the excess charged particles that often appear during extreme space weather events – particles that could disrupt radio waves and/or the power grid, The Atlantic said.
Image credit: NASA