NASA and LBNL Use AI and X-Rays to Observe Heat Shield Ablation in Real-Time

• NASA and Lawrence Berkeley National Laboratory (LBNL) have developed a method to observe spacecraft heat shields decomposing during reentry in real-time.
• Researchers utilized Generative Adversarial Networks (GANs) to bridge the gap between imaging speed and resolution for high-quality 3D data.

The Ablation Process

• Ablation is a vital process where heat shield material absorbs thermal energy and sheds pieces to protect the spacecraft during atmosphere reentry.
• Missions like Artemis I revealed discrepancies between pre-flight simulations and real-world results, such as unexpected charring and uneven material loss.

Research Methodology

• The study used a specialized chamber at the Advanced Light Source (ALS) capable of reaching 900℃ while mimicking reentry atmospheric conditions.
• X-ray micro-computed tomography (micro-CT) was employed to capture 3D structural changes in real-time as materials warped and charred.

Comparative Material Behavior

• SLA-561V (with natural cork filler): Cork particles vaporize rapidly, forming hollow voids within the material structure.
• SLA-220 (silicone-elastomer matrix): Degrades into complex, interconnected micro-channels that allow hot gases to vent efficiently.

Future Implications

• Findings have not yet been integrated into standard aerospace engineering simulations used for predicting heat shield performance.
• Commercial proprietary technologies, such as SpaceX's PICA-X and reusable ceramic tiles, remain to be studied using this advanced technique.