Deep space travel could cause serious, irreversible brain damage, NBC News reports. Scientists have long known that leaving Earth’s magnetosphere—the magnetic bubble of plasma surrounding our planet—strips astronauts of their protection from radioactive particles, putting them at higher risk for health issues, including heart disease. Now, a new study out this week in Scientific Reports suggests that changes at the cellular level could also lead to worsened anxiety and even brain cancer. That could be bad news for NASA and other commercial space companies that want to send humans to the Red Planet by 2030. But NASA is working on it: The agency is researching methods to prevent exposure to radiation, which could find their way into new, improved space suits.