Search Publications
The Impact of Energetic Particles on the Martian Ionosphere During a Full Solar Cycle of Radar Observations: Radar Blackouts
Witasse, Olivier; Orosei, Roberto; Lester, Mark +13 more
We present the first long-term characterization of ionization layers in the lower ionosphere of Mars (below ∼90 km), a region inaccessible to orbital in-situ observations, based on an analysis of radar echo blackouts observed on Mars Express and the Mars Reconnaissance Orbiter from 2006 to 2017. A blackout occurs when the expected surface reflecti…
What Is Unusual About the Third Largest Geomagnetic Storm of Solar Cycle 24?
Gopalswamy, N.; Yashiro, S.; Mäkelä, P. +4 more
We report on the solar and interplanetary (IP) causes of the third largest geomagnetic storm (26 August 2018) in solar cycle 24. The underlying coronal mass ejection (CME) originating from a quiescent filament region becomes a 440 km/s magnetic cloud (MC) at 1 au after ∼5 days. The prolonged CME acceleration (for ∼24 hr) coincides with the time pr…
Global Three-Dimensional Draping of Magnetic Field Lines in Earth's Magnetosheath From In-Situ Spacecraft Measurements
Lavraud, B.; Génot, V.; Jeandet, A. +4 more
Magnetic field draping occurs when the magnetic field lines frozen in a plasma flow wrap around a body or plasma environment. The draping of the interplanetary magnetic field (IMF) around the Earth's magnetosphere has been confirmed in the early days of space exploration. However, its global and three-dimensional structure is known from modeling o…
Jovian Auroral Electron Precipitation Budget—A Statistical Analysis of Diffuse, Mono-Energetic, and Broadband Auroral Electron Distributions
Saur, J.; Mauk, B. H.; Salveter, A. +1 more
Recent observations by the Juno spacecraft have shown that electrons contributing to Jupiter's main auroral emission appear to be frequently characterized by broadband electron distributions, but also less often mono-energetic electron distributions are observed as well. In this work, we quantitatively derive the occurrence rates of the various el…
Magnetosheath Jet Occurrence Rate in Relation to CMEs and SIRs
Geyer, Paul; Temmer, Manuela; Plaschke, Ferdinand +6 more
Magnetosheath jets constitute a significant coupling effect between the solar wind (SW) and the magnetosphere of the Earth. In order to investigate the effects and forecasting of these jets, we present the first-ever statistical study of the jet production during large-scale SW structures like coronal mass ejections (CMEs), stream interaction regi…
Massive Multi-Mission Statistical Study and Analytical Modeling of the Earth's Magnetopause: 1. A Gradient Boosting Based Automatic Detection of Near-Earth Regions
Lavraud, B.; Jeandet, A.; Aunai, N. +3 more
We present an automatic classification method of the three near-Earth regions, the magnetosphere, the magnetosheath and the solar wind from their in situ data measurement by multiple spacecraft. Based on gradient boosting classifier, this very simple and very fast method outperforms the detection routines based on manually set thresholds. The meth…
Relation of Jupiter's Dawnside Main Emission Intensity to Magnetospheric Currents During the Juno Mission
Nichols, J. D.; Cowley, S. W. H.
We compare Jupiter's dawn-side main auroral emission intensity observed by the Hubble Space Telescope with the simultaneous magnitude of the dawn-side magnetospheric equatorial radial current as observed by Juno during Orbits 3-7. We show that the peak auroral intensity and the square of the radial current per radian of azimuth are strongly correl…
Massive Multi-Mission Statistical Study and Analytical Modeling of the Earth's Magnetopause: 2. Shape and Location
Lavraud, B.; Jeandet, A.; Aunai, N. +3 more
The Earth magnetopause is the boundary between the magnetosphere and the shocked solar wind. Its location and shape are primarily determined by the properties of the solar wind and interplanetary magnetic field (IMF) but the nature of the control parameters and to what extent they impact the stand-off distance, the flaring, and the symmetries, on …
The Influence of Crustal Magnetic Fields on the Martian Bow Shock Location: A Statistical Analysis of MAVEN and Mars Express Observations
Garnier, P.; Génot, V.; Halekas, J. S. +6 more
Previous missions underlined the complex influence of the crustal magnetic fields on the Martian environment, including the plasma boundaries. Their influence on the bow shock is however poorly constrained, with most studies showing North/South differences attributed to the crustal fields, with various conclusions from little to strong variabiliti…
The Wave Telescope Technique
Glassmeier, K. -H.; Narita, Y.; Motschmann, U.
Unambiguous determination of wavevectors (wavelengths and propagation directions) is one of the major challenges of space plasma observations, since conventional wave analysis methods for the single spacecraft data are limited to the time series data analysis and the wave properties are determined as a function of the frequencies in the spacecraft…