How and why do charged particles cause corrosion of materials in space? This is a question asked by many spacecraft engineers and the answer is not so simple. Namely, there is a whole zoo of different particles and every single one of them interacts with the matter in a unique way. The general rule however is that particles which have a higher mass, charge and velocity, cause more damage. For instance, electrons have a negative charge and in a scanning electron microscope they travel at about 20% of the speed of light but they hardly damage the studied substrate. Ions however have not only a charge but also a lot of mass and therefore they can also cause serious damage if their velocity is sufficient. A completely different story is with antimatter particles such as positrons and anti-protons. When these hit regular matter, then both the particle and the surface of regular matter is converted into energy in the form of gamma radiation. This radiation however can ionize the nearby matter and also do serious damage to electronics, which is shielded from particles but not from gamma rays. High energy radiation is also created when regular charged particles such as protons and electrons interact with the matter as the excess energy is released as braking light (bremsstrahlung), when the high velocity of the particle suddenly changes to zero upon hitting the surface of a material. Anyhow, the spacecrafts are constantly being bombarded with different particles and this slowly degrades the surface of the material and the resulting radiation also has a devastating effect on the electronics. Learn more by watching our new science video: