A mixed-up region of sunspots pointed almost directly at Earth has just emitted a major solar flare, which could cause havoc with power grids and communication networks over the next few days.
NASA’s Solar Dynamic Observatory (SDO) first detected the sunspot area designated AR3006 (“AR” stands for “active region”) several days ago; now the region is located near the center of the sun’s visible disk. SDO images show a spot near the region’s center has the reverse magnetic polarity of the surrounding area– meaning its magnetic field lines are pointing the opposite direction than the field lines nearby. This mismatch creates an unusual situation that can cause major disturbances, called “magnetic reconnections,” when the areas of differing polarity interact.
And it now seems that interaction has happened. Earth-orbiting satellites have detected a radio burst indicating an X1.5 class flare erupted from AR3006 shortly before 9 a.m. ET (1400 Universal Time) on Tuesday (May 10). Experts told Live Science that the resulting flare is impressive, though not necessarily that unusual.
It’s likely the flare also caused a coronal mass ejection (CME), launching a blob of plasma mixed-up that could impact Earth in the next few days. There are five classes of solar flare: A, B, C, M and X, according to NASA. Each is 10 times more powerful than the previous class, and they’re followed by a number from 1 to 9 that indicates their strength within that class. But there’s theoretically no limit to the strength of the largest X-class flares: The most powerful on record, from 2003, overwhelmed the sensors at a classification of X28
jan Janssens, a communications specialist at the Solar-Terrestrial Centre of Excellence in Brussels – which coordinates international efforts to monitor the sun – called the new solar flare “impressive.” But “I’m a bit surprised by the strength of the flare, because all this concerned only small sunspots,” Janssens told Live Science in an email.
AR3006 is a relatively small patch of sunspots developing in the remnants of a decaying active region, but its structure of mixed polarities means that it has a higher likelihood of snapping and releasing gobs of energy into space, he said. Solar physicist Dean Pesnell of NASA’s Goddard Space Flight Center, the project scientist for the Solar Dynamics Observatory, said the mixed polarity of the AR 3006 region was not uncommon. “It happens when the twisted magnetic field lines flip around under the surface before erupting,” Pesnell told Live Science in an email, adding that solar flares also seemed more common in regions with such complicated magnetic fields.
CMEs typically emit billions of tons of stellar material at speeds of hundreds of miles a second, according to the NOAA’s Space Weather Prediction Center. If CME material from the latest flare impacts Earth in the next few days it has the potential to disrupt electricity grids and communications networks, and to damage satellites. At the moment the sunspot region is pointed almost directly toward us, Janssens noted, but any risk of disruption from the CME will lessen over the next few days as AR3006 rotates towards the western edge of the sun’s visible disk. Pesnell explained mixed-up that determining whether a CME would hit Earth was a “difficult and interesting calculation” that depends on the location and the dynamics of the CME filament. Whereas such events were “clues to how the solar dynamo operates,” Pesnell said, “we only see the results of the dynamo, rather than the actual mechanism.” “It’s like trying to understand the water cycle on Earth by only looking at the cloud tops and not knowing about the precipitation and oceans underneath,”
Source: This news is originally published by livescience