Research and Application News
How heavy oxygen ions escape Earth’s gravity
05 April 2018
A new study reveals that low-frequency electromagnetic waves accompany intense heating events at low altitudes.
On 17 December 1971, scientists observed a bizarre new phenomenon in the outermost region of Earth's atmosphere, where the planet's magnetic field orchestrates the flow of charged particles and produces such phenomena as auroras. In the midst of a massive geomagnetic storm induced by a surge of solar radiation, satellites detected large flows of heavy oxygen (O+) ions streaming away from Earth, seemingly in defiance of gravity. Ever since, scientists have been trying to figure out what propelled the ions, in part because disturbances in this zone—known as the ionosphere—can disrupt communication systems. A new study by Shen et al. reveals for the first time how low-altitude electromagnetic waves help launch these ions toward outer space.
Image credit: Canadian Space Agency - CASSIOPE/e-POP satellite passing over Earth's nightside aurora