On June 14th, for the second day in a row, sunspot AR1504 erupted and hurled a Coronal Mass Ejection toward Earth. Spaceweather.com says the fast-moving (1360 km/s) cloud is expected to sweep up a previous CME and deliver a combined blow to Earth’s magnetic field on June 16th around 10:16 UT. So, high latitude skywatchers should be on the lookout for possible aurorae.
This same active region has been producing several C-class solar flares and five M-class solar flares the past week, and has now developed a ‘beta-gamma-delta’ magnetic field that harbors energy for strong solar flares. NOAA forecasters estimate a 65% chance of M-flares and a 5% chance of X-flares during the next 24 hours.
Thanks to the Solar Dynamics Observatory, scientists can keep an eye on all this activity. The top video starts off with a view from June 9 to 12 in the 171 angstrom wavelengths, showing coronal loops extending off of the Sun where plasma moves along magnetic field lines, and then shows the flares in 304 angstrom.
A shape-shifting active region; AR1504 rotated over the eastern limb of the Sun on June 9 and started its journey across the Earth facing side of the Sun with a M-class solar flare. Between June 9 and 14 a total of 5 M-class flares were observed, of which the long-duration June 13 flare hurled a coronal mass ejection (CME) our way.
Below is a view of the sunspots in optical wavelengths. Sunspots can last weeks or months, but they do eventually disappear, often by breaking into smaller and smaller sunspots.