This paper explores the mechanisms and risk factors of cataract formation in two high-risk groups: radiotherapy patients and astronauts. Despite differences in radiation exposure, both groups experience cataractogenesis through similar mechanisms, such as DNA damage and oxidative stress. Unique risk factors, such as microgravity for astronauts, are compared with the high-dose exposure of radiotherapy patients. The study highlights the need for tailored preventive measures, including antioxidant therapy and shielding technologies.