Related Experiment Video
Updated: Feb 19, 2026

Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Dayside response of the magnetosphere to a small shock compression: Van Allen Probes, Magnetospheric MultiScale, and
C Cattell1, A Breneman1, C Colpitts1
1School of Physics and Astronomy University of Minnesota, Twin Cities Minneapolis Minnesota USA.
Abstract:
Observations from Magnetospheric MultiScale (~8 Re) and Van Allen Probes (~5 and 4 Re) show that the initial dayside response to a small interplanetary shock is a double-peaked dawnward electric field, which is distinctly different from the usual bipolar (dawnward and then duskward) signature reported for large shocks. The associated E × B flow is radially inward. The shock compressed the magnetopause to inside 8 Re, as observed by Magnetospheric MultiScale (MMS), with a speed that is comparable to the E × B flow. The magnetopause speed and the E × B speeds were significantly less than the propagation speed of the pulse from MMS to the Van Allen Probes and GOES-13, which is consistent with the MHD fast mode. There were increased fluxes of energetic electrons up to several MeV. Signatures of drift echoes and response to ULF waves also were seen. These observations demonstrate that even very weak shocks can have significant impact on the radiation belts.
More Related Videos
Related Concept Videos
Magnetostatic Boundary Conditions
Magnetism
An individual magnetic pole cannot be isolated. No matter how small, every piece of a magnet contains a north pole and a south...
Potential Due to a Magnetized Object
The vector...
Magnetic Susceptibility and Permeability
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
Magnetic Fields
A magnetic field is defined by the force that a charged particle experiences...
Magnetic Field Lines
Magnetic field lines follow several hard-and-fast rules:

