A moderate G2 geomagnetic storm sparked auroras at mid-latitudes, and we've rounded up some of the best northern lights photos here.

In effect, Fig. 3c, d shows that a poleward fast-moving bright aurora slows down and dims after the expansion phase, recedes to lower latitudes, then fades away during late substorm recovery phase.

Evolution of Energetic Proton Parallel Pressure Anisotropy at Geosynchronous Altitudes: Potential Role in Triggering Substorm Expansion Phase Onset ...

The sounding rockets released vapor tracers and pressure sensors at different altitudes across central and northern Alaska during a sudden auroral substorm.

Watch the northern lights and elusive STEVE light up the skies above Manitoba, Canada in these stunning photos and footage captured by astrophotographer Justin Anderson.

The project, catchily named Auroral Waves Excited by Substorm Onset Magnetic Events (AWESOME), was led by researchers from the University of Alaska Fairbanks (UAF).

Hwang et al. report observations using the Cluster spacecraft and ground-based magnetometers associated with the onset of a substorm. They saw two consecutive sudden jumps in the current sheet ...

Ultrafast Substorm Auroras Explained** Synopsis: From time to time, sudden releases of energy in Earth’s magnetosphere lead to major disturbances that result in bright auroral displays over the ...

They cannot account for some observations of substorm events, which indicate that aurorae intensify less than 1 minute after the onset of reconnection — much earlier than expected.

Magnetic substorms, the disruptions in geomagnetic activity that cause brightening of aurora, may sometimes be driven by a different process than generally thought, a new study in the Journal of ...