A man takes pictures of the Aurora, also known as the southern lights, glow on the horizon over the … [+]
I told you it was going to be a good night for the aurora borealis and the aurora australis, but no one expected it to be this good.
Cracks in Earth’s magnetic shields and a coronal hole on the sun allowed a big blast of charged particles from the solar wind to trigger a severe G4-class geomagnetic storm, putting on a big show in the skies late Thursday and early Friday.
The event is the strongest solar storm seen in over five years. Bright dancing Northern Lights were reported as far south as North Carolina and Phoenix, Arizona, nearly stretching across the Mexican border.
Further north, the lights were exceedingly spectacular:
The space weather forecast had been for a moderate G2 geomagnetic storm thanks to the solar wind streaming through that coronal hole and what’s considered “aurora season” around the equinox. This time of year presents an ideal geometry of the solar wind and earth’s magnetic field to give the aurora a boost.
Exactly why the storming went from moderate to severe overnight isn’t quite clear. Astronomer Dr. Tony Phillips at Spaceweather.com says the effects from a near miss by a coronal mass ejection (CME) from the sun could be to blame.
CMEs are blasts of charged plasma from the sun’s outer layers that cause some of the most spectacular auroras when they collide with our magnetosphere.
The storm lasted for the better part of 24 hours, peaking around midnight and into the early morning hours, Eastern Daylight Time.
The space weather forecast for the weekend has things settling down a bit, but then again, this event went well and beyond forecast expectations, so it’s worth keeping an eye on the sky.
In addition to being aurora season, we’re also in the midst of a solar cycle that’s ramping towards a peak of intensity over the next couple years. This means an increase in sunspot activity, which means more solar flares and CMEs to trigger high energy light shows.
