It may be called The Land of the Rising Sun, but in terms of geography theres a lot more to Japan. Its also set on the Ring of Fire, which puts it in direct contact with multiple fault lines and over a hundred volcanoes. Its a wonder that the whole country isnt ablaze at all times but that doesnt mean that every volcano is willing to stay quiet.
Mount Aso is set on one of Japans main islands, and is usually a popular spot for tourism. But the sudden eruption of the mountain dissuaded any visits; black smoke reached more than a mile into the air, while ash has reportedly fallen as far as two and a half miles away from the mountain. As a result, the area has been evacuated and no one is allowed entry a sore point for tourists, but a welcome safety measure.
Incidentally, the eruption hasnt caused any deaths or even injuries, and itll likely stay that way thanks to the evacuation. Its a lucky break; there were no earthquakes or emissions from the volcano beforehand, so Asos eruption was likely the result of an explosion pressed forward by water flowing below. More to the point, the peoples safety is as much good fortune as it is a testament to good protocol or failing that, strong survival instincts.