Researchers at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have created a technique to observe how spacecraft heat shields break down in real time under extreme temperatures. The study, published in the journal npj Materials Degradation, used a method called in situ X-ray micro-computed tomography (micro-CT) to take time-lapse 3D images of heat shield materials as they underwent ablation. Ablation is a process where materials degrade or burn away to protect the spacecraft and its crew during reentry into Earth's atmosphere. The research simulated the intense conditions of atmospheric reentry by heating samples to temperatures as high as 1,652 degrees Fahrenheit (900 degrees Celsius). The study focused on two types of heat shield materials used in spacecraft backshells: SLA-220 and SLA-561V. These materials have different compositions and are used in different parts of spacecraft. SLA-561V includes cork as a structural filler, which decomposes when heated, leaving behind open spaces. SLA-220, on the other hand, uses a rubber-like silicone matrix that forms a dense network of interconnected channels when exposed to high temperatures. These structural differences influence how each material performs as a heat shield during reentry. To capture both broad views of the samples and detailed microscopic changes, the researchers used an AI-based super-resolution technique powered by generative adversarial networks. This method allowed them to enhance the entire sequence of images taken during the experiment, resulting in a high-resolution record of how each material changed throughout the heating process. The findings offer direct measurements of how heat shield materials alter at a microscopic level under the extreme thermal conditions of atmospheric reentry. These insights help improve models used to predict material behavior, which is essential for ensuring the safety and reliability of future crewed space missions, such as NASA's Artemis and Mars entry programs. The research emphasizes the importance of understanding the internal structural changes that occur during ablation, a challenge that has previously limited the ability to fully analyze heat shield performance.