Dynamical development of strength and stability of asteroid material under 440 GeV proton beam irradiation

Abstract

Asteroid materials experience rapid thermoelastic and plastic stress evolution when subjected to high-energy irradiation – an effect that has not previously been captured through non-destructive, time-resolved experiments. Yet, accurate modeling of asteroid deflection scenarios, such as those proposed for planetary defense, critically depends on precise knowledge of the material’s mechanical behavior under extreme conditions to predict kinetic energy transfer and orbital deviation. In an experimental campaign at CERN’s High Radiation to Materials facility (HiRadMat), we irradiated a Campo del Cielo iron meteorite sample with 440 GeV protons from the Super Proton Synchrotron. Using Laser Doppler Vibrometry, we captured the resulting thermally induced stress waves in real time. Our results demonstrate that asteroid materials can absorb significantly more energy without structural failure than normal material parameters would suggest. Crucially, we were able to reproduce–under controlled laboratory conditions–the discrepancy factor observed between laboratory-derived yield strength values and those inferred from atmospheric meteor breakup events.

Understanding asteroid materials is critical for determining deflection methods for planetary defense. Here the authors show, via experiments performed in High-Radiation to Materials facility at CERN, that iron-rich asteroid materials can absorb more energy without structural failure than standard material parameters would suggest.