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Life Sciences at NASA: Risk Identification and Mitigation

In preparation for sending humans back to the Moon, Mars, and Beyond, scientists want to make sure that they fully understand the risks involved. A trip to Mars will take at least 30 months, or two and a half years! During this time, astronauts will be in a weightless environment also known as microgravity. They will also be exposed to harmful radiation from the Sun.

Astronaut Peggy Whitson exercises on the International Space StationImagine if you were to lie down in bed for two and a half years without ever getting up! What do you think might happen to your body?

Your bones would lose mass and get weaker.

Your muscles, because they are not used, would get weaker.

Your heart would not have to pump blood against gravity, so it would become weaker.

Similar things happen to astronauts when they are exposed to weightlessness in space for a long time. Since their bodies adapt to the weightless conditions, they are fine when they're in space.

Life scientists understand how human body systems behave in normal conditions; they are starting to understand the adaptations to spaceflight, but the big question is how and if they re-adapt to Earth normal conditions. Problems occur, however, when the astronauts return to Earth, or another place with gravity (like Mars). When they try to stand, sometimes their bones and muscles cannot support their weight. Their heart is not used to pumping fluid against gravity, so astronauts who have been in space for a long time often faint when they try to stand up. This is a problem, since astronauts need to be in good physical condition to land vehicles on Earth, the Moon, or Mars.

Life sciences researchers try to figure out the risks of traveling in space and how to reduce them. For example, exercising on a treadmill can help keep bones and muscles strong. Eating a healthy diet with proper vitamins and minerals also contributes to keeping astronauts healthy.

The sun, depicting a coronal mass ejection.Another risk that astronauts are exposed to is increased radiation from the sun. On Earth, the ozone layer in our atmosphere protects us by keeping the harmful radiation out. In space, astronauts travel above this layer, so they have to be very careful. Increased exposure to radiation could cause cancer or other health problems that are not fully understood.

In summary, NASA's life sciences researchers are trying to figure out the risks of long-duration spaceflight. Once the risks are identified, they try to figure out how to reduce them to keep the astronauts healthy. Some of the risks include exposure to microgravity and radiation.

Now that you have an idea about the life science research NASA explores, it's time to learn about some experiments NASA is sending into space!

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 FirstGov  NASA
Editor: Carol Elland
NASA Official: B J Navarro
Last Updated: September 2006
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