NASA’s Solar Dynamics Observatory, or SDO, has captured an image of a gigantic sunspot, which rotated from the left side of the sun to the right on Oct. 18. The sunspot soon grew to be the largest active region observed in the current solar cycle -- a periodic change in the sun's activity and appearance -- which began in 2008.
The sunspot region, dubbed AR 12192, is about 80,000 miles across, which is wide enough for 10 Earths to be laid across its diameter, according to NASA. The sunspot, which is visible to the naked eye from Earth, has produced several significant solar flares over the last few days, including an X-class flare on Sunday, an M-class flare on Tuesday and another X-class flare on Wednesday.
“This is the largest sunspot group since November of 1990,” Doug Biesecker, a researcher at the National Weather Service Space Weather Prediction Center told The Washington Post, which also reported, citing The Sun Today, that AR 12192’s size is 2,740 millionths of the solar disc, which is nearly the size of Jupiter.
According to astronomers, sunspots are comparatively cooler areas on the sun with powerful magnetic fields poking out through the sun's surface. Such areas are also the source of solar eruptions, such as flares and blasts of plasma known as coronal mass ejections that can lead to auroras in the Earth’s atmosphere and disrupt satellites, global positioning systems and communications signals.
“A typical sunspot region has a north and south pole but some are more complex with polarity mixed together,” Biesecker told the Post. Sunspot region AR 12192 “has some of that mixed polarity, but this region isn’t as scary as the region associated with the Halloween solar storm of 2003 which was more complex.”
According to NASA, the largest sunspot, observed in 1947, was almost three times as large as AR 12192. Active regions on the sun are more common at the moment as the sun is in its “solar maximum” stage, a phase that occurs every 11 years and denotes the peak of the sun's activity.