The sun was in a good mood this week, or at least that's what it looked like in a photo published by NASA. A photo of the sun taken from a NASA satellite and time-stamped Thursday morning appears to show a smile on the surface of our nearest star. It's not the first time this week the cheerful pattern appeared. "Today, NASA’s Solar Dynamics Observatory caught the sun 'smiling.'" NASA said in a Wednesday tweet. "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." Read more about the sun at the link in our bio.