On August 20 and again on August 21, the sun released coronal mass ejections (CMEs), giant plumes of plasma that are heading towards Earth.
Courtesy of ESA & NASA / SOHO
Right now, Earth is in the path of not one but two coronal mass ejections (CMEs). One burst from the sun's surface early Tuesday morning, moving fast, and the other left not long after midnight early Wednesday morning, moving more slowly.
When the sun erupts a huge burst of matter and energy like this, the particles can fly anywhere between 200 and 1000 miles per second, says Art Poland, an astrophysicist with George Mason University. Tuesday morning's CME was moving at 570 miles per second, NASA reported, and Wednesday's was a more sedate 380 miles per second. The charged particles from the earlier CME may already be in our atmosphere, while Wednesday's particles could reach us by midnight Friday night (Eastern Time).
Solar flares, like coronal mass ejections, follow the sun's 11-year sunspot cycle, and right now, we're near the peak of solar activity. "At solar minimum we observe about one CME a week. Near solar maximum we observe an average of 2 to 3 CMEs per day," reports NASA's CME website. That's including CMEs shooting out in any direction, but these two are heading towards Earth, which means the situation in our skies could get interesting soon.