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.
Northern Lights Now – A large polar-connected coronal hole will bring high speed solar wind to Earth starting August 4th and SWPC has posted a G2 geomagnetic storm watch. The watch means it is possible that aurora activity as measured by KP may reach 5.67 during the August 4th UTC day (from 8pm EST on 8/3 through 8pm EST on 8/4). The watch period extends into August 5th at a slightly lower activity level with G1 storming predicted.
The coronal hole responsible for this activity is large. It extends from the polar region to the Southern Hemisphere of the Sun:
Earth is expected to travel through the area of high speed solar winds sometime on Friday. Any disturbances carried on the wind stream with a negative oriented Bz could make for strong aurora activity. Keep any eye on the solar wind data, there should be a period of increased activity in Bt and Bz before the actual arrival.
The current timing and forecast for this storm calls for the G1 and G2 storming late on the 4th followed by G1 storming through midday on the 5th as winds subside. As always, these forecasts can be +/-12 hours, so the best bet is to keep an eye on the data or the Northern Lights Now Twitter feed, to know when it is best to go out.
The Moon is waxing gibbous – which means it will be visible and bright in the evening and set after midnight. The best aurora viewing times will be in the wee hours after the Moon sets.
Northern Lights Now – A large, long duration M2.44 Solar flare launched an Earth-directed CME from the surface of the Sun early on July 14 that may make for a period of active aurora on July 16 and 17. The NOAA Space Weather Prediction Center (SWPC) has issued a G2 storm watch for both days indicating that the aurora activity readings could be as high as KP=5.67. There is a chance that this storm could reach G3 storm levels.
NLN will be activating an Aurora live blog over the next several days, so come back often for updates. For starters, here is a quick animation of the flare that generated the CME that will impact Earth.