A recent study may have thrown a serious wrench into potential space travel aspirations. Apparently, all those cosmic rays are seriously hazardous to brain health and can cause permanent cognition impairments. As NASA plans to send astronauts on a long-term journey to Mars as early as the 2030s, this is a factor that astronauts will need to take into consideration.

At the NASA Space Radiation Laboratory at the Brookhaven National Laboratory in New York, Charles Limoli, a professor of radiation oncology at the University of California, Irvine School of Medicine, and his team tested the effect of deep space conditions on the brains of rodents. According to the press release, the scientists subjected the rats to charged particle irradiation (fully ionized oxygen and titanium) in New York before sending them back to California to study.

Results showed that the charged particles had serious and long-lasting effects on the brain of the rats. Firstly, the exposure caused inflammation in the brain, which disrupted the transmission of signals among neurons. Also, brain images revealed there were physical changes to the central nervous system, with reductions in the structure of dendrite nerve cells and the spine. This caused disruptions in the brain’s communication network.

If the damage recorded in the rats was translated into a human model, then it would be parallel to decreased performance on behavioral tasks designed to test learning and memory. The damage would be similar to that observed in cancer patients who have undergone various photon-based radiation treatments.

What This Means For Space Travel

Scientists are beginning to learn just how dangerous space travel will actually be to the human body. However, while the physical effect of space on the body may be deadly, that doesn’t mean space travel is completely impossible. Limoli predicted that it would take months before astronauts would be subjected to this brain damage, so the danger is only in scientists who go on extended space journeys, such as the planned mission to Mars.

The damage is caused by highly energetic charged particles given off by cosmic rays. Theoretically, having a spaceship specifically built to shield these particles would protect the astronauts’ brains on these long missions. Unfortunately, this would only be a partial solution, because according to Limoli, “there is really no escaping them,” and the rays would eventually make their way past the shield.

Instead of working to block the rays from entering the brain, Limoli suggests developing a pharmaceutical approach to protecting the brain from their damages. This drug would be able to scavenge free radicals and protect neurotransmission in the brain.

Source: Limoli CL, Parihar VK, Allen B. What happens to your brain on the way to Mars. Science Advances. 2015.