Generating Sawtooth Oscillations

This Week in Science: Highlights of Research in Science Journals

Editor's summary of "Magnetosphere Sawtooth Oscillations Induced by Ionospheric Outflow" by Oliver Brambles, William Lotko et al.

Credit: Brambles et al.

Earth's magnetosphere is subject to sawtooth oscillations as it responds to the constant battering of the solar wind, the stream of charged particles coming from the Sun. Although observations have uncovered many of the properties of this type of disturbance, the mechanism that generates it is unclear. Based on numerical simulations of the interaction of the solar wind with the magnetosphere and the ionosphere, Brambles, Lotko et al. now show that the flow of O+ ions from the ionosphere to the magnetosphere can produce sawtooth oscillations.