To the left, a close-up view of Sunspot 484 from the MDI instrument on SOHO; to the right, a close-up of a coronal mass ejection billowing out from the Sun into space from the LASCO instrument. Credit: NASA/ESA
This week researchers have been observing an enormous sunspot the size of Jupiter. As a result of associated flares, NOAA predicts strong geomagnetic storms to hit Earth on Friday with the potential to affect electrical grids and satellite communications. Aurora may be visible as far south as Oregon and Illinois. Meanwhile, scientists are watching another large sunspot rotate toward us with potential for even more powerful and prevalent explosions.
Sunspot 484 seems to have appeared as a reminder that the Sun's 11-year solar max period is not over yet. One of the largest sunspot of the cycle, it is the size of 11 Earths and has been generating stormy solar activity, hurling clouds of electrified gas towards Earth, producing explosions, or flares, and spawning storms of high-speed particles in space.
Sunspots are darker areas on the visible surface of the Sun caused by a concentration of distorted magnetic fields. They are slightly cooler than their surroundings, which make them appear darker.