The region of space around the Earth occupied by its magnetic field is called the magnetosphere. The innermost layer of the magnetosphere is the ionosphere and above that is the plasma sphere. Plasma created by the atmosphere ionised by sunlight floats in the inner layer in different shapes including the tubes.
For over 60 years, scientists believed these structures existed but did not have any visual proof. Cleo Loi of the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) and the School of Physics at the University of Sydney has for the first time captured visual evidence of the existence of tubular plasma structures in the inner layers of the magnetosphere surrounding the Earth by using the Murchison Widefield Array, a radio telescope in the Western Australian desert. Loi is the lead author of a research for undergraduate thesis which was published in the journal Geophysical Research Letters. Her work had won Loi the 2015 Bok Prize of the Astronomical Society of Australia.
The radio telescope had rapid snapshot capability using which she mapped large patches of the sky effectively capturing the real-time movements of the plasma. The plasma tubes were positioned 600 km above the ground, in the upper ionosphere, continuing upwards into the plasmasphere.
The study is important because these structures cause unwanted signal distortions that could affect civilian and military satellite-based navigation systems.