What lies deep beneath our feet—or inside distant planets—is one of the greatest mysteries in science. The interior structure of Earth and other planets holds the key to their past and future evolution, yet it remains beyond direct reach. To uncover these hidden realms, we recreate planetary interiors in the laboratory using high-pressure mineral physics—squeezing and heating materials to the extreme conditions found thousands of kilometers below the surface. In this talk, I will present two examples showing how these experiments help answer fundamental questions. First, I will show how oceanic crust, once formed at mid-ocean ridges, can be transported to depths of nearly 2,000 km inside the Earth—revealing how surface materials cycle through the deep mantle. Second, I will explore how the iron-water reaction can alter the density and structure of super-Earths, offering new perspectives on the diversity of large rocky planets.

Yanyao Zhang investigates the interior structures of Earth and other planets through high-pressure laboratory experiments. He earned his Ph.D. in Geological Sciences from the University of Texas at Austin and his M.S. in Geochemistry from Peking University. Since 2023, he has been a postdoctoral scholar at Stanford University.