The surface of the sun is constantly changing. To make sure it doesn’t miss anything, NASA’s Solar Dynamics Observatory (SDO) spacecraft is constantly taking photos of the sun.
One of the three instruments aboard the spacecraft, the four-telescope Atmospheric Imaging Assembly, is especially prolific; it takes a mind-boggling 57,000 photos a day. And at 12:49 p.m. ET on Jan. 19, 2015, it snapped its 100 millionth photo.
