For over six decades, scientists have speculated that there might be structures of plasma residing in the upper atmosphere of Earth, affecting civilian and military satellite-based navigation systems. Thanks to Australian researcher, Cleo Loi, this theory has been confirmed.
Researchers in Australia have now created a 3D map of images of plasma tubes for the first time, discovering evidence at first deemed “too good to be true.”
So, what exactly is going on here? The magnetic field surrounding the Earth, the magnetosphere, is inundated with plasma, i.e. ionized gas consisting of positive ions and free electrons in proportions that produce no electric charge. Plasma is produced when the atmosphere is ionized by incoming sunlight. The innermost layer of the magnetosphere is called the ionosphere, and above it resides the plasmasphere. Plasma structures take on a variety of strange forms within these regions including the now-documented plasma tubes.
And why is this significant? This is significant for a number of reasons. First off, these structures are the likely cause of unwanted signal distortions that affect our navigation systems. Secondly, it offers an unprecedented glimpse of the odd plasma formations that arise in the Earth’s atmosphere. This is the first time that scientists have directly observed these plasma tubes over a large scale and mapped their shape.
The discovery was made by a 23-year old astrophysics student, Cleo Loi, at the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) and School of Physics at the University of Sydney. Loi is also the lead author in the paper documenting the discovery, published in the scientific journal, Geophysical Research Letters.
“We measured their position to be about 600 kilometres [373 miles] above the ground, in the upper ionosphere,” Loi said. “And they appear to be continuing upwards into the plasmasphere. This is around where the neutral atmosphere ends, and we are transitioning to the plasma of outer space. We saw a striking pattern in the sky where stripes of high-density plasma neatly alternated with stripes of low-density plasma. This pattern drifted slowly and aligned beautifully with the Earth’s magnetic field lines, like aurorae.”
By separating the western and eastern sides and triangulating their output in a way that is similar to how the left eye and right eye work, she was able to create a visual representation of the tubes in the magnetic field.
“We were able to measure the spacing between them, their height above the ground and their steep inclination,” says Loi. “This has never been possible before and is a very exciting new technique.”
Loi has since been awarded the 2015 Bok Prize of the Astronomical Society of Australia for her exemplary work.