NASA is planning a return to the Moon and an exploration-mission to Mars, but how will the human body hold up in microgravity for long durations?

In a Tech Briefs presentation titled The Next Giant Leap: Back to the Moon and On to Mars, an attendee had the following question for NASA's Deborah M. Tomek:

"There are some biological changes and disruptions to the human body when humans stay in space for a long time. One of them is ocular pressure, especially if we go to Mars, which would be a multiyear mission, or if we stay on the Moon for prolonged period of time. People run the risk of going blind, or at least having their vision severely impacted. The ocular pressure symptoms are similar to glaucoma, which would impact mission success and astronauts health. What is NASA doing to address the biological changes and disruptions to the human body when humans stay in space for a long time?"

Read Tomek's edited response below.

Deborah M. Tomek, Deputy Director, Space Technology and Exploration Directorate, NASA Langley Research Center: You are exactly right. Simply put, our bodies are not designed to survive in space. There has been a large amount of research that has been going on for years on how we can develop these technologies and keep crews safe for sustained presence and long-duration stays either on the surface or in space.

I will take it even a step further. The eye/ocular issue is one of many. There is space radiation exposure, and what that does biologically on a cellular level. Together with NASA and also heavy input from academia and industry, we have a program called the Human Research Program (HRP) . HRP looks at all of these different elements across the human body.

We actually learned a lot with twin astronauts Scott and Mark Kelly . One spent a year in space; the other stayed terrestrial here on the surface of the Earth. [NASA] did comparative analysis between them. That research is still ongoing, as they are looking at the effects on Scott's body during the one year in space, to understand how it changes. Whether it’s the effect on our bones due to microgravity, whether it’s issues with blindness, whether it’s the higher instances of cancer based on the space radiation and exposure to solar particle events — these are just a few of the things that affect our bodies.

We have dedicated programs to actually study these effects. We haven’t completely solved them. The program is called a "research program" for a reason. We are continuing to learn, but those are some of the big hurdles that we have to overcome if we indeed want to have a long-duration human presence in space.

I’m confident that we can solve these problems. We just need more time to do it. We'll need commercial partners. It's all the more important for us to bring in folks who have made advancements in these areas, and for us to partner with either industry or academia, or partner with others globally who can help us solve these problems together.

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