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Quadratic Magnetic Gradients From Seven- And Nine-Spacecraft Constellations

Shen, Chao; Kieokaew, Rungployphan; Zeng, Gang +1 more

To uncover the dynamics of magnetized plasma, it is crucial to determine the geometric structure of the magnetic field, which depends on its linear and quadratic spatial gradients. Estimating the linear magnetic gradient requires at least 4 simultaneous magnetic measurements, while calculating the quadratic gradients generally requires at least 10…

Investigation Of The Occurrence Of Significant Deviations In The Magnetopause Location: Solar-Wind And Foreshock Effects

Plaschke, Ferdinand; Grimmich, Niklas; Pöppelwerth, Adrian +7 more

Common magnetopause models can predict the location of the magnetopause with respect to upstream conditions from different sets of input parameters, including solar-wind pressure and the interplanetary magnetic field. However, recent studies have shown that some effects of upstream conditions may still be poorly understood since deviations between…

Estimating Gradients Of Physical Fields In Space

Shen, Chao; Zhou, Yufei

This study focuses on the development of a multi-point technique for future constellation missions, aiming to measure gradients at various orders, in particular the linear and quadratic gradients, of a general field. It is well established that, in order to estimate linear gradients, the spacecraft must not lie on a plane. Through analytical explo…

Does High-Latitude Ionospheric Electrodynamics Exhibit Hemispheric Mirror Symmetry?

Hatch, Spencer Mark; Vanhamäki, Heikki; Magnus Laundal, Karl +6 more

Ionospheric electrodynamics is a problem of mechanical stress balance mediated by electromagnetic forces. Joule heating (the total rate of frictional heating of thermospheric gases and ionospheric plasma) and ionospheric Hall and Pedersen conductances comprise three of the most basic descriptors of this problem. More than half a century after iden…

Impact Ionization Double Peaks Analyzed In High Temporal Resolution On Solar Orbiter

Meyer-Vernet, Nicole; Mann, Ingrid; Vaverka, Jakub +6 more

Solar Orbiter is equipped with electrical antennas performing fast measurements of the surrounding electric field. The antennas register high-velocity dust impacts through the electrical signatures of impact ionization. Although the basic principle of the detection has been known for decades, the understanding of the underlying process is not comp…

Low-Frequency Solar Radio Type II Bursts And Their Association With Space Weather Events During The Ascending Phase Of Solar Cycle 25

Ndacyayisenga, Theogene; Uwamahoro, Jean; Uwamahoro, Jean Claude +5 more

Type II solar radio bursts are signatures of the coronal shocks and, therefore, particle acceleration events in the solar atmosphere and interplanetary space. Type II bursts can serve as a proxy to provide early warnings of incoming solar storm disturbances, such as geomagnetic storms and radiation storms, which may further lead to ionospheric eff…

The Cluster Spacecrafts' View Of The Motion Of The High-Latitude Magnetopause

Darrouzet, Fabien; Plaschke, Ferdinand; Grimmich, Niklas +10 more

The magnetopause is the boundary between the interplanetary magnetic field and the terrestrial magnetic field. It is influenced by different solar-wind conditions, which lead to a change in the shape and location of the magnetopause. The interaction between the solar wind and the magnetosphere can be studied from in situ spacecraft observations. M…

Scalar-Potential Mapping Of The Steady-State Magnetosheath Model

Toepfer, Simon; Narita, Yasuhito; Schmid, Daniel

The steady-state magnetosheath model has various applications for studying the plasma and magnetic field profile around the planetary magnetospheres. In particular, the magnetosheath model is analytically obtained by solving the Laplace equation for parabolic boundaries (bow shock and magnetopause). We address the question, how can we utilize the …

Machine learning detection of dust impact signals observed by the Solar Orbiter

Mann, Ingrid; Vaverka, Jakub; Soucek, Jan +8 more

This article presents the results of automatic detection of dust impact signals observed by the Solar Orbiter - Radio and Plasma Waves instrument.

A sharp and characteristic electric field signal is observed by the Radio and Plasma Waves instrument when a dust particle impacts the spacecraft at high velocity. In this way, ∼ 5-20 dust impacts …

Effects of ion composition on escape and morphology on Mars

Zhang, Qi; Holmström, Mats; Wang, Xiao-Dong

We refine a recently presented method to estimate ion escape from non-magnetized planets and apply it to Mars. The method combines in situ observations and a hybrid plasma model (ions as particles, electrons as a fluid). We use measurements from the Mars Atmosphere and Volatile Evolution (MAVEN) mission and Mars Express (MEX) for one orbit on 1 Ma…