Search Publications
The Vertical Extent of Enhanced Densities in Cusp Like Regions of the Ionosphere of Mars
Kopf, A. J.; Withers, P.; Golden-Marx, E.
Unusually large values of peak electron density in the ionosphere of Mars are occasionally observed in cusp like regions of crustal magnetic field. These features are observed as atypical examples of oblique echoes in ionograms. However, the vertical extent over which electron density values are enhanced has not yet been determined. Furthermore, t…
Turning Instrument Background Into Science Data for Structural Features of Radiation Belts
Dandouras, I.; Rème, H.; Liemohn, M. W. +2 more
Approaches regarding how to turn the instrument background counts into scientifically valuable data are presented in this Technical Report on Methods. The background counts due to penetrating energetic particles of radiation belts detected on Cluster CIS HIA and CODIF instruments and the Double Star HIA instrument are used in these approaches. In …
Impact of the Solar Wind Dynamic Pressure on the Field-Aligned Currents in the Magnetotail: Cluster Observation
Dandouras, I.; Dunlop, M. W.; Rème, H. +6 more
We statistically investigate the influence of the solar wind dynamic pressure (SW Pdyn) on the field-aligned currents (FACs) in the magnetotail with 1,492 FAC cases from July to October in 2001 and 2004, which covers 74 Cluster crossings of the plasma sheet boundary layer (PSBL) in both storm time and non-storm time. The FAC density in …
In Which Magnetotail Hemisphere is a Satellite? Problems Using in Situ Magnetic Field Data
Gunell, H.; Hamrin, M.; Pitkänen, T. +2 more
In Earth's magnetotail plasma sheet, the sunward tailward Bx component of the magnetic field is often used to separate the region above and below the cross tail current sheet. Using a three dimensional magneto hydrodynamic simulation, we show that high speed flows do not only affect the north south magnetic field component (causing dipo…
Quantitative Assessment of Protons During the Solar Proton Events of September 2017
Pandya, Megha; Bhaskara, Veenadhari
We present multi-spacecraft observations of the proton fluxes spanning from 1.5 to 433 MeV for the largest solar proton event of solar cycle 24, i.e., September 7 and 10, 2017. In September 2017, M5.5 flare on September 4, X9.3 flare on September 6 and X8.2 flare on September 10 gave rise to solar proton event when observed by near-Earth spacecraf…
Small-Scale Magnetic Structures: Cluster Observations
Gedalin, Michael; Walker, Simon N.; Balikhin, Michael A. +2 more
Within the inner magnetosphere, the occurrence of plasma waves and/or magnetic field structures plays an important role in the dynamics of the particle populations, accelerating some particles to higher energies while scattering others. The 2013 Cluster Inner Magnetosphere Campaign was designed to investigate this process based on observations mad…
Particle Dynamics in the Earth's Radiation Belts: Review of Current Research and Open Questions
Li, X.; Ukhorskiy, A. Y.; Fennell, J. F. +4 more
The past decade transformed our observational understanding of energetic particle processes in near-Earth space. An unprecedented suite of observational systems was in operation including the Van Allen Probes, Arase, Magnetospheric Multiscale, Time History of Events and Macroscale Interactions during Substorms, Cluster, GPS, GOES, and Los Alamos N…
Atmospheric Escape Processes and Planetary Atmospheric Evolution
Simon Wedlund, C.; Maggiolo, R.; Cessateur, G. +17 more
The habitability of the surface of any planet is determined by a complex evolution of its interior, surface, and atmosphere. The electromagnetic and particle radiation of stars drive thermal, chemical, and physical alteration of planetary atmospheres, including escape. Many known extrasolar planets experience vastly different stellar environments …
Magnetic Reconnection in the Space Sciences: Past, Present, and Future
Hesse, M.; Cassak, P. A.
Magnetic reconnection converts, often explosively, stored magnetic energy to particle energy in space and in the laboratory. Through processes operating on length scales that are tiny, it facilitates energy conversion over dimensions of, in some cases, hundreds of Earth radii. In addition, it is the mechanism behind large current disruptions in fu…
Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis
Lugaz, N.; Winslow, R. M.; Salman, T. M.
Our knowledge of the properties of coronal mass ejections (CMEs) in the inner heliosphere is constrained by the relative lack of plasma observations between the Sun and 1 AU. In this work, we present a comprehensive catalog of 47 CMEs measured in situ measurements by two or more radially aligned spacecraft (MESSENGER, Venus Express, STEREO, Wind/A…