Tokyo Tech Lecture Theatre: "Magic Class" lecture for high school students

Institute Professor Akio Hosoya

"Are there any students in the room today who haven't seen the moon?" Hosoya began. After a lengthy silence, he continued. "Of course not, suggesting something of that sort would be lunatic."

Earth is the only planet with such a large moon relative to its size, and the radioisotopic composition of moon rock is exactly like that found on Earth. How can that be? The giant impact hypothesis suggests that, approximately 4.5 billion years ago, an astronomical body the size of planet Mars collided with Earth, spewing debris into space. This debris then gathered to form the moon we know today. It sounds unbelievable, but it is a theory supported by results of computer simulations, Hosoya explained. At pivotal points of the lecture, graduate student Yuhito Shibaike helped with supplementary explanations and assisted in answering questions from the audience.

Institute Professor Hitoshi Tokura

After Hosoya's lecture, Institute Professor Hitoshi Tokura continued with his talk entitled "Grains of Wonder." Tokura explained that grains are everywhere. Some grains, like the sand in an hourglass, are visible, and other grains, like those in car paint, are not. While introducing students to the scanning electron microscope, he demonstrated the ever-changing characteristics of grains and explained how this makes their application extremely varied.

"Let's try to measure how compact grains can get. I am going to pack this cup as full of rice grains as I can. Next, I will add water and see how much the weight increases."

The audience was satisfied with the results, all viewable with the ceiling visualizer. Even after the lecture, many students were still gathered around the electron microscope, clearly intrigued.