Monday, September 25, 2006

Mission To Mars

"Say again, Base Command? I don't understand. What do you want me to do? What am I looking for? Mars is too big. I can't find base-camp. Oh, we should never have come." The commander panicked as he realised he was lost, and he couldn't understand Base's instructions. It had only been a half an hour since he had taken off in search of the caves, and he had headed his rover in a straight path toward the designated coordinates, but something was wrong. He should have reached the caves by now. He should have seen the double peak just to the right of Sydney crater, which marked the opening to the series of caverns that Earth Command had sent him to explore, and now, when he knew he should be right on target, he was completely turned around. He couldn't even trace back along the route he had followed to relocate camp.

How could he have gotten so disoriented? He had only been driving for half an hour. Or was it half an hour? He looked intently at his watch and tried to remember exactly what the time had been when he left the confines of the Mars Base habitat. Memory failed him, despite the intense pressure he put on himself to think. Think. Why was that getting so much harder lately? Every day further into space had been more of a struggle on the long journey from Earth. He couldn't think clearly. Base-camp wasn't any help; none of them were doing any better than he was. Why was he feeling such anxiety? Why couldn't he remember even what time he had set out? Why hadn't he seen the landmarks he knew were right there? Somewhere.

The poor commander was really only a few hundred meters from his desired destination, but couldn't figure out where he was, or remember how to get home. Why? Radiation. Radiation can potentially cause problems with memory, spacial learning, and stress, according to an article by David Shiga, at New Scientist Space. Radiation. Space is full of it. We have a built-in defense from radiation here on Earth. A haven from the bombardment from space, our atmosphere protects us from much of its harmful effects. Even orbiting astronauts, tucked away up in the International Space Station, or jaunting about in a shuttle, or rocket, are kept safe from the dangers of most of the stray energy particles from space by the extended shielding of the Earth's magnetic field. What happens. though, if we leave the protection of our big blue marble?

NASA is looking to find out. According to Shiga, "...NASA recently awarded funding for 12 projects that will investigate how long-term radiation exposure in interplanetary space could potentially cause health problems in astronauts." Some of these projects are serving up some interesting results. One study, by Bernard Rabin of the University of Maryland in Baltimore, involves studying irradiated rats:

Rats whose brains have been exposed to heavy particle radiation perform more poorly in navigating mazes and have a harder time learning to press a button to get a food pellet. They also are more easily distracted and experience more anxiety in stressful situations.
One of the more intriguing findings in this study is that rats given strawberry and blueberry extracts before receiving the radiation were less likely to have their mental function impaired. The speculation in Shiga's article is that the anti-oxidants in the berries are the protectant factor:

This could be because the extracts contain antioxidants. Researchers still do not know exactly how heavy particle radiation creates cognitive problems, but it is known to create highly reactive oxygen-containing molecules in the body.

So-called reactive oxygen species are suspected as a contributor to the ageing process. As it turns out, the problems the rats encounter from radiation exposure are very similar to those that ageing rats experience, Rabin says.

Maybe if they just feed astronauts on an anti-oxidant rich diet, they won't suffer any ill effects from space radiation, and they won't get any older. Heck of a deal. (Unless that not getting any older involves not getting any older, if you know what I mean, or is that too obscure?) Anyway, the point of the NASA funding for these types of projects is partly to find out just how much radiation is tolerable, so they can design spaceships and missions which will keep the radiation exposure within acceptable limits. I'm sure they have other studies going on to determine exactly how to do that, what materials to use, what time parameters to establish, what Lunar and Martian materials may be adapted to astronaut use, as well as a whole host of studies designed just to help them think up more questions and possible scenarios, that will need further studies to come up with the answers.

While they are doing all this, I hope they stay away from sources of radiation themselves. We've seen what can happen to people who aren't properly shielded. If it weren't for the help of a friendly alien who happened to be passing by, our commander might still be wandering around Mars. Fortunately, the alien, from the lovely planet Gardenium, found him and led him back to base-camp. The other-worldly savior also brought them a token of good will--an eighteen month supply of strawberries and blueberries. Wasn't that a nice thing to do?