Search Publications
The unexpected origin of plasmaspheric hiss from discrete chorus emissions
Meredith, Nigel P.; Thorne, Richard M.; Bortnik, Jacob
Plasmaspheric hiss is a type of electromagnetic wave found ubiquitously in the dense plasma region that encircles the Earth, known as the plasmasphere. This important wave is known to remove the high-energy electrons that are trapped along the Earth's magnetic field lines, and therefore helps to reduce the radiation hazards to satellites and human…
A magnetic reconnection X-line extending more than 390 Earth radii in the solar wind
Balogh, A.; McComas, D. J.; Reme, H. +8 more
Magnetic reconnection in a current sheet converts magnetic energy into particle energy, a process that is important in many laboratory, space and astrophysical contexts. It is not known at present whether reconnection is fundamentally a process that can occur over an extended region in space or whether it is patchy and unpredictable in nature. Fre…
Space Physics: Breaking through the lines
Paschmann, Götz
Magnetic field lines are known to reorganize themselves in plasmas, converting magnetic to particle energy. Evidence harvested from the solar wind implies that the scale of the effect is larger than was thought.
Wave acceleration of electrons in the Van Allen radiation belts
Meredith, Nigel P.; Horne, Richard B.; Glauert, Sarah A. +11 more
The Van Allen radiation belts are two regions encircling the Earth in which energetic charged particles are trapped inside the Earth's magnetic field. Their properties vary according to solar activity and they represent a hazard to satellites and humans in space. An important challenge has been to explain how the charged particles within these bel…
In situ multi-satellite detection of coherent vortices as a manifestation of Alfvénic turbulence
Sundkvist, David; Vaivads, Andris; Krasnoselskikh, Vladimir +4 more
Turbulence in fluids and plasmas is a ubiquitous phenomenon driven by a variety of sources-currents, sheared flows, gradients in density and temperature, and so on. Turbulence involves fluctuations of physical properties on many different scales, which interact nonlinearly to produce self-organized structures in the form of vortices. Vortex motion…
Magnetospheric physics: Turbulence on a small scale
Goldstein, Melvyn L.
The four-spacecraft Cluster mission has identified small-scale vortices in Earth's magnetosphere. The observation reveals processes that transfer energy and momentum from the solar wind to the magnetosphere.
Transport of solar wind into Earth's magnetosphere through rolled-up Kelvin-Helmholtz vortices
Balogh, A.; Hasegawa, H.; Fujimoto, M. +5 more
Establishing the mechanisms by which the solar wind enters Earth's magnetosphere is one of the biggest goals of magnetospheric physics, as it forms the basis of space weather phenomena such as magnetic storms and aurorae. It is generally believed that magnetic reconnection is the dominant process, especially during southward solar-wind magnetic fi…
Continuous magnetic reconnection at Earth's magnetopause
Fuselier, S. A.; Mende, S. B.; Frey, H. U. +1 more
The most important process that allows solar-wind plasma to cross the magnetopause and enter Earth's magnetosphere is the merging between solar-wind and terrestrial magnetic fields of opposite sense-magnetic reconnection. It is at present not known whether reconnection can happen in a continuous fashion or whether it is always intermittent. Solar …
Temporal evolution of the electric field accelerating electrons away from the auroral ionosphere
Balogh, A.; André, M.; Buchert, S. +10 more
The bright night-time aurorae that are visible to the unaided eye are caused by electrons accelerated towards Earth by an upward-pointing electric field. On adjacent geomagnetic field lines the reverse process occurs: a downward-pointing electric field accelerates electrons away from Earth. Such magnetic-field-aligned electric fields in the collis…
Space physics: Rhythms of the auroral dance
Newell, Patrick T.
Earlier this year, the four satellites of the Cluster mission passed through part of the electric circuit that causes aurorae. Their observations support the view that intense aurorae form in regions largely devoid of electrons.