Who among us, if we got the chance, would refuse a trip into space? No one, that’s who. Because even though you’d have to sit on top of a rocket powerful enough to overcome Earth’s gravity and more than one person has died when things didn’t go right, the chance to see our little blue ocean planet from 200 miles up is too tantalizing to reject.
Too bad all space wants to do is mess you up.
We’ve known for a while that space travel can have some big effects on the body, most notably on the bones. But a new study indicates that deep space travel may cause Alzheimer’s disease.
Researchers at the University of Rochester Medical Center blasted mice with irradiated iron ions, the same ions that would pummel astronauts zooming through space on their way to, say, Mars. The mice absorbed the equivalent radiation relative to their size as a human would receive on a two-to-three year Mars mission. What they found was downright terrifying.
The irradiated mice were much more likely to suffer memory loss. More terrifying? The irradiated mice had a buildup of something called amyloid beta, which is an indication of Alzheimer’s disease in both humans and rats. This could be due to damage done to the DNA which keeps the brain’s immune response from functioning properly.
Space Alzheimer’s? Great.
We’ve been traveling in space for a while now. How come we haven’t seen these effects in our non-rodent astronauts? It has to do with the type of particle we’re dealing with. These iron ions are heavy, much heavier than the hydrogen protons produced by solar flares from our sun, and blasted out of supernovae. They are so big and powerful, in fact, that they can bust through conventional shields. To protect yourself you’d need a six foot wall of lead or concrete.
(In case you’re wondering why we don’t have problems with this type of radiation here on Earth, you have the planet’s magnetic field to thank.)
There are, of course, limits to what this experiment can tell us. According to the study, the mice were given all the radiation in one dose. It’s unknown how a low, chronic dose of galactic cosmic radiation will effect actual human beings. In addition, it’s unlikely that all astronauts will have Alzheimer’s in their genetic background. So the study is illuminating, but not the be-all end-all of research into the effects of cosmic rays on these 21st century explorers.
Image credit: NASA