Northern Lights Now – Just a couple days before the 2017 total eclipse in the United States, there will be another exciting astonomical event. There is a chance for Aurora on August 17 and 18. The Space Weather Prediction Center (SWPC) has issued a G1 geomagnetic storm watch for Wednesday and Thursday. Global aurora activity levels could reach KP=5 on the 0-9 scale.
The expected activity is the result of a activity from a solar sector boundary crossing during high speed solar wind stream arriving from a coronal hole. The northern hemisphere coronal hole (below) pointed towards Earth on August 15th is releasing solar winds in excess of 650 km/s. The winds, and the plasma and solar particles carried on them will start to arrive early on 8/17
Embedded in the solar wind there will be disturbance along the solar sector boundary. This is basically a line on the in space between a positively charged region and a negatively charged region. As the boundary passes Earth, there will be enhanced geomagnetic activity leading to Northern Lights.