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Rippled Quasiperpendicular Shock Observed by the Magnetospheric Multiscale Spacecraft
A Johlander1,2, S J Schwartz3,4, A Vaivads1
1Swedish Institute of Space Physics, Uppsala 75121, Sweden.
Physical Review Letters
|October 30, 2016
Summary
Earth's bow shock exhibits nonstationarity, appearing as ripples. This finding, observed using Magnetospheric Multiscale (MMS) spacecraft data, helps quantify microscale physics influencing space plasma phenomena.
Area of Science:
- Space Physics
- Plasma Physics
- Astrophysics
Background:
- Collisionless shock nonstationarity, driven by microscale physics, impacts shock structure and particle acceleration.
- Quantifying nonstationarity is challenging due to its small spatial and temporal scales.
Purpose of the Study:
- To investigate and quantify nonstationarity in Earth's quasiperpendicular bow shock.
- To compare competing nonstationarity processes using high-resolution spacecraft data.
Main Methods:
- Utilizing closely spaced, high-time-resolution measurements from the Magnetospheric Multiscale (MMS) spacecraft.
- Analyzing high-cadence kinetic plasma data during a rapid bow shock crossing.
Main Results:
- The study reveals nonstationarity in the bow shock.
- Nonstationarity manifests as observable ripples on the shock structure.
Conclusions:
- The Magnetospheric Multiscale (MMS) mission provides crucial data for studying shock nonstationarity.
- Ripples represent a key feature of nonstationarity in collisionless shocks, offering insights into microscale physics.
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