A collision between an interplanetary disturbance in the solar wind and the heliospheric termination shock leads to the generation and propagation of plasma structures in the inner heliosheath (IHS). This interaction can lead to one or more shocks propagating in the IHS until they collide with the heliopause (HP).
The leading hypothesis for the origin of the Interstellar Boundary Explorer (IBEX) "ribbon" of enhanced energetic neutral atoms (ENAs) from the outer heliosphere is the secondary ENA mechanism, whereby neutralized solar wind ions escape the heliosphere, and after several charge-exchange processes, may propagate back toward...
The solar wind emitted from the solar corona is a highly ionized plasma composed of electrons, protons, He2+ ions, and a small fraction of heavier ions. Additionally, interstellar neutral (ISN) atoms ionized in the heliosphere form populations of pickup ions (PUIs). The two most abundant PUIs are of H+ and He+.
Parisa Mostafavi who is working with Prof Dave McComas as a Visiting Student Research Collaborator won the Graduate Research Award in the College of Science of the University of Alabama in Huntsville.
Since crossing the heliopause on 2012 August 25, Voyager 1 observed reductions in galactic cosmic ray count rates caused by a time-varying depletion of particles with pitch angles near 90°, while intensities of particles with other pitch angles remain unchanged. Between late 2012 and mid-2017, three large-scale events occurred, lasting from ~...
The Moon is continually bombarded by interplanetary meteoroids. While many of the meteoroid sources are near the ecliptic plane, a significant population of high-inclination meteoroids exists at 1 au that bombards the lunar polar regions.
Airless bodies in the solar system are continually bombarded by meteoroids, sustaining impact ejecta clouds. While large bodies like the Moon retain a significant fraction of ejecta, small asteroids shed this material into the interplanetary dust complex. Measurements of the lunar impact ejecta cloud found it was sustained by the known sporadic...
The Interstellar Mapping and Acceleration Probe (IMAP) is a revolutionary mission that simultaneously investigates two of the most important overarching issues in Heliophysics today: the acceleration of energetic particles and interaction of the solar wind with the local interstellar medium.
On Oct. 3, 2018, Parker Solar Probe performed the first significant celestial maneuver of its seven-year mission.