It has long been known that there are many obstacles to launching a successful mission to Mars, not least of which is building a craft capable of handling the long journey out there. Now, researchers have discovered yet another complicating factor for the ongoing effort to reach the Red Planet: cosmic rays emanating from supernovas have been found to bear radiation effects that could significantly damage astronauts' brains.
A study published Friday in Science Advances posited that astronauts making extended interplanetary jaunts could suffer from cognitive damage. In coming to that conclusion, a research team led by Charles Limoli, a UC Irvine neuroscientist and professor of radiation oncology, studied the effects of space radiation on mouse brains.
To simulate the idea of mouse brains in space, the scientists exposed mice to oxygen and titanium ions--which bear properties similar to the charged particles found in cosmic rays in outer space--at New York's NASA's Space Radiation Laboratory at the Brookhaven National Laboratory. Six weeks later, in California, they conducted memory and learning tests on the mice: by exposing them to new environments and gradually introducing new toys into their ecosystem, and studying their responses.
They found that the mice who had been exposed to the simulated radiation were less cognizant of or even completely unfazed by changes around them, or by familiar objects, suggesting that there had been a cognitive break due to the radiation. When researchers studied the mice's brain tissues, their suspicions proved correct: the less curious mice had suffered structural changes in their brains, and their brain cells showed significantly less branching. These so-called branches, which stem from neurons, are critical to brain function.
If exposed to similar conditions, researchers determined, astronauts' brains could suffer cognitive consequences. In a statement, Limoli said: "Over the course of a two- to three-year mission, the damage would accumulate." While the damage isn't suspected to be extraordinary, any kind of cognitive impairment that could cause astronauts to lose focus during a mission of this magnitude is troubling.
Limoli suggested that the only way to mitigate this damage would be to conduct further research in an attempt to understand and address the radiation problems, since there's no way to completely evade them. Scientists are exploring shields, such as helmets, that could help to assuage the intense effects of radiation, as well as heavily padding sleeping areas to keep radiation out. Drug treatments used for cancer patients undergoing radiation therapy may also be a possibility.
No word yet on any potential Mars attacks, though.
