Kovaltsov, G. A. & Usoskin, I. G. Occurrence probability of large solar energetic particle events: assessment from data on cosmogenic radionuclides in lunar rocks. (nature.com)
MAVEN's Solar Energetic Particle instrument was able to observe the onset of the event that day. (sciencedaily.com)
Solar energetic particles from these events can easily penetrate typical shielding and damage spacecraft electronics and biological cells. (sciencedaily.com)