Just before Halloween, on October 27, 2022, NASA had shared an image of the smiling Sun. It was simply awesome, a Sun smiley! However, the mood of the fireball seems to have changed now, soured in fact! There has been a complete U-turn in the Sun's mood and it has soured unimaginably, presenting a terrifying spectacle. NASA on Tuesday shared the image of the Sun's face of fury on its Twitter handle. Sharing the image NASA tweeted, "After last month's smiley face, the Sun's mood seems to have…soured."
Earlier, while sharing the Sun's smiling face, NASA informed that the dark patches which have formed the eyes and the smile of the Sun are the coronal holes. "Today, NASA's Solar Dynamics Observatory caught the Sun "smiling." Seen in ultraviolet light, these dark patches on the Sun are known as coronal holes and are regions where fast solar wind gushes out into space," the tweet read.
Giving further insights regarding the smiling face image of the Sun, the US agency on November 10 said that the solar wind gushing from each of the eyes of the Sun in the image was streaming at over 370 miles per second. "Another #FunFact is that the solar wind gushing from each of the "eyes" in this image was streaming at over 370 miles per second! This super-fast solar wind is called a high speed stream," the tweet read.
Meanwhile, for the uninitiated, coronal holes appear as dark areas in the solar corona in extreme ultraviolet (EUV) and soft x-ray solar images. They appear dark because they are cooler, less dense regions than the surrounding plasma and are regions of open, unipolar magnetic fields. This open, magnetic field line structure allows the solar wind to escape more readily into space, resulting in streams of relatively fast solar
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