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Global Response of Martian Plasma Environment to an Interplanetary Structure: From Ena and Plasma Observations at Mars

Barabash, S.; Lundin, R.; Futaana, Y. +4 more

As a part of the global plasma environment study of Mars and its response to the solar wind, we have analyzed a peculiar case of the subsolar energetic neutral atom (ENA) jet observed on June 7, 2004 by the Neutral Particle Detector (NPD) on board the Mars Express satellite. The "subsolar ENA jet" is generated by the interaction between the solar …

Shocks: Commonalities in Solar-Terrestrial Chains

Schwartz, Steven J.

Shocks are found throughout the heliosphere, wherever supersonic (or super-magnetosonic) flows encounter obstacles or other, slowly moving, media. Although some of the physical parameters are in different regimes, all shocks heat and decelerate the media incident upon them. Most shocks must propagate in a collisionless plasma, thereby adding impor…

Asymmetries in Mars' Exosphere. Implications for X-ray and ENA Imaging

Holmström, Mats

Observations and simulations show that Mars' atmosphere has large seasonal variations. Total atmospheric density can have an order of magnitude latitudinal variation at exobase heights. By numerical simulations we show that these latitude variations in exobase parameters induce asymmetries in the hydrogen exosphere that propagate to large distance…

Energisation of O⁺ and O⁺ ₂ Ions at Mars: An Analysis of a 3-D Quasi-Neutral Hybrid Model Simulation

Kallio, E.; Fedorov, A.; Janhunen, P. +12 more

We have studied the loss of O⁺ and O⁺₂ ions at Mars with a numerical model. In our quasi-neutral hybrid model ions (H⁺, He⁺⁺, O⁺, O⁺₂) are treated as particles while electrons form a massless charge-neutralising fluid. The employed model version does not includ…

Substorms and Their Solar Wind Causes

Nakamura, Rumi

Consequences of the solar wind input observed as large scale magnetotail dynamics during substorms are reviewed, highlighting results from statistical studies as well as global magnetosphere/ionosphere observations. Among the different solar wind input parameters, the most essential one to initiate reconnection relatively close to the Earth is a s…

Observations of the Martian Subsolar ENA Jet Oscillations

Fedorov, A.; Barabash, S.; Futaana, Y. +1 more

The Neutral Particle Detector (NPD) of the ASPERA-3 experiment (Analyser of Space Plasmas and Energetic Atoms) on board the Mars Express (MEX) spacecraft observed an intense flux of H ENAs (energetic neutral atoms) with average energy of about 1.5 keV emitted anisotropically from the subsolar region of Mars. The NPD detected the ENA jet near the b…

Review of Ionospheric Effects of Solar Wind Magnetosphere Coupling in the Context of the Expanding Contracting Polar Cap Boundary Model

Wild, J. A.; Lester, M.; Milan, S. E. +1 more

This paper reviews the coupling between the solar wind, magnetosphere and ionosphere. The coupling between the solar wind and Earth’s magnetosphere is controlled by the orientation of the Interplanetary Magnetic Field (IMF). When the IMF has a southward component, the coupling is strongest and the ionospheric convection pattern that is generated i…

Cross-Scale Coupling Within Rolled-Up MHD-Scale Vortices and Its Effect on Large Scale Plasma Mixing Across the Magnetospheric Boundary

Hasegawa, H.; Fujimoto, M.; Nakamura, T. K. M.

Kelvin-Helmholtz Instability (KHI) is an MHD-scale instability that grows in a velocity shear layer such as the low-latitude boundary layer of the magnetosphere. KHI is driven unstable when a velocity shear is strong enough to overcome the stabilization effect of magnetic field. When the shear is significantly strong, vortices in the nonlinear sta…

Supermassive Black Holes in Galactic Nuclei: Past, Present and Future Research

Ford, Holland; Ferrarese, Laura

This review discusses the current status of supermassive black hole research, as seen from a purely observational standpoint. Since the early ‘90s, rapid technological advances, most notably the launch of the Hubble Space Telescope, the commissioning of the VLBA and improvements in near-infrared speckle imaging techniques, have not only given us i…

The Foreshock

Eastwood, J. P.; Lucek, E. A.; Narita, Y. +4 more