We are treated to these visual displays because of charged particles (electrons, protons) that are ejected from the Sun and make their way to Earth as the solar wind. These charged particles follow the Earth's magnetic fields (think of a bar magnet!) and enter near the poles. The Sun has an activity cycle, ie times when it is more active -- more sunspots -- which can trigger larger eruptions called coronal mass ejections (CMEs). These CMEs, which can wreak havoc on our electrical grid, can sometimes produce auroral activity as far south as Louisiana but this is rare. Living in Canada, I was fortunate to witness many auroral displays.
If you've ever seen the Northern Lights, and especially if you have not, you must check out this video constructed from time-lapse photography! Ole Christian Salomonsen has spent the last 6 months, snapping nearly 50,000 photos, chasing these beautiful displays near his hometown of Tromso, Norway. Imagine seeing this on the big dome in high resolution!
Shanil Virani
In The Land Of The Northern Lights from Ole Christian Salomonsen
