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Aurora borealis: charged particles in Earth's dipole field

What you are seeing: the solar wind injects charged particles into Earth's dipole magnetic field; they gyrate around field lines, bounce between magnetic mirror points, and where they dip into the upper atmosphere near the magnetic poles they excite oxygen to glow green (lower aurora) and red (higher aurora). Drag to rotate

Figure 1. Charged particles spiraling along Earth's dipole field, exciting the auroral oval. Method: Boris pusher (symplectic Lorentz integration); dipole B⃗∝(3(r^⋅z^)r^−z^)/r3\vec B \propto (3(\hat r \cdot \hat z)\hat r - \hat z)/r^3; atmospheric excitation triggered below 600 km near the poles.
injection rate3
dipole strength1.4
animation speed2
cameradrag to orbit, wheel to zoom

WHAT TO TRY

  • Vary each control and watch the rail readouts respond.
  • Compare the diagnostic plot against the live scene.