Aurora chasers are on alert after NOAA's Space Weather Prediction Center (SWPC) issued a moderate (G2) geomagnetic storm watch for Friday (Aug. 28), as coronal mass ejections (CMEs) launched from the sun yesterday (Aug. 25) head toward Earth.
The CME arrival follows a powerful M6.9 solar flare from restless sunspot region 4513 on Aug. 25. NOAA's SWPC has also issued a minor (G1) geomagnetic storm watch for Thursday (Aug. 27), as a stream of fast solar wind from a coronal hole is expected to buffet Earth ahead of the incoming CMEs
The M6.98 solar flare erupted from the active sunspot region 4513 and peaked at 6 a.m. EDT (1000 GMT), according to SpaceWeatherLive. 4513 has been particularly active over the previous 24 hours, firing off a barrage of solar flares including five powerful M-class eruptions. Solar flares are ranked by strength into five classes — A, B, C, M and X — with each class 10 times more powerful than the one before it. M-class flares are the second-strongest category, sitting just below the most powerful X-class eruptions.