In February 2022, an American space exploration company simultaneously launched 49 satellites. Yet not long after, 40 of those satellites fell out of orbit and burned up upon re-entry into the Earth's atmosphere. Similar accidents have occurred frequently in the past. The cause of such incidents is believed to be solar flares, huge explosions that occur on the sun's surface. Solar flares can also lead to other disasters that threaten our daily lives, such as major power outages, radio interference, and communication problems for airplanes and ships. Why do solar flares occur? We'll visit some researchers in Japan that are working hard to understand their mechanism and predict future occurrences.