Scientists on Friday, stated that cosmic radiation during the deep-space voyage, is likely to affect astronaut’s brain. The rays can cause subtle brain damage in astronauts, leaving them confused, forgetful and slow to react to the unexpected.
The NASA-funded study was conducted on mice, and was published in Science Advances by researchers at University of California and University of Nevada. The creatures were exposed to a few weeks equivalent of space radiation, and made them perform poorly in tests of learning, memory as it damaged the brain cells. Researchers stated that the prolonged bombardment by charged particles could affect the brain cells in decision-making and memory, affecting manned missions into space.
“These sorts of cognitive changes could manifest during the mission and could be the real problem,” said Cary Zeitlin at the Southwest Research Institute in San Antonio.
In 2013, Zeitlin had reported that the radiation levels between Earth and Mars, measured by Mars Science Laboratory craft was the equivalent of getting a “whole body CT scan” once every five or six days. The cosmic rays, mix of gamma rays, high-energy protons, make up the unique deep-space radiation. The cosmic rays are deflected fro the Earth due to its atmosphere and magnetic field while spacecrafts are shielded.
However, in 54 years of manned missions, astronauts are yet to experience the full dose of radiation. Apollo crews reported flashes of light when they closed their eyes, indicating cosmic rays speeding through the eyes. The effect of the radiation is being studied by NASA for decades, though it has been hard to simulate the behavioral effects of prolonged exposure to low-levels of radiation.
NASA stated in a letter that the agency understood the importance of the effects of radiation on humans, and future studies were expected to help the manned mission to Mars. Though spacecraft can be shielded, they can become heavy, and also increases the cost of the mission.[ Source ]