Before revision: Instead of moisture and oxygen acting as the primary corrosion causes, the materials exposed to outer space are subjected to vacuum, bombardment by ultraviolet and X-rays, and high-energy charged particles (mostly electrons and protons from solar wind) .
After revision: Instead of moisture and oxygen acting as the primary corrosion causes, the materials exposed to outer space are subjected to vacuum, bombardment by ultraviolet and X-rays, , and electromagnetic radiation charged particles (mostly electrons and protons from solar wind) .