Isn't Betelgeuse, the giant star in Orion, suddenly shining intensely one day? Expectations are rising now. This is because the last "supernova explosion" caused by an old star is imminent. If it explodes, it will be 100 times brighter than the full moon. At the end of 2019, Betelgeuse dimmed rapidly. What the hell is going on? The latest research has also revealed that it is a "odd star" that goes far beyond common sense. It conveys the forefront of exploring the life of a mysterious star.