In her short videos, 72-year-old Wu Yuren often uses everyday objects like eggs, hangers, and coins as props for her experiments. In one video for example, when explaining cosmic rays in space, she grabbed a broom, ran her hand down the broomstick to the thin brush attached, to illustrate how the energy of the rays gradually weakens and disperses. Using a cooking pot, she introduced China’s Five-hundred-meter Aperture Spherical Radio Telescope (FAST); she also explained rocket launches by blowing up a balloon. These intriguing science videos have attracted over 1 million followers. She’s now quite famous on China’s social media,...