Wayne Hale’s NASA Blog: Serendipity – Part 5

I’m going to round out this little series on the serendipity of space travel with a discussion of what we have learned about the human body in space. There are probably a thousand blogs that I could write on the serendipity of space travel so we will come back to this topic in the future.

Before 1961 the medical community was almost unanimous that space travel would be fatal to human beings. Not only would it be impossible to swallow food or water without the affect of gravity, but the circulatory system would completely break down, fluids accumulate in the wrong places and the heart would not be able to pump blood adequately.

Early flights with mammals and then primates showed significant changes and while the animals generally survived, there were serious questions. The first few manned flights were nail biters. Fortunately everybody came back alive. And some of the worst predictions were quickly shown to be false; for example swallowing is as much a function of peristalsis as it is gravity. But serious changes in the human body did show up.

For exposure to zero gravity for a week or two, the human body showed remarkable adaptation ability. But there were several close calls and many warning signs that things would not be well for longer duration flights. The Skylab flights concentrated on trying to understand some of these changes and came back with alarming results. Subsequently, many Space Shuttle flight experiments and studies refined the issues. The redistribution of fluids in the cardiovascular system, changes in the structure of the bones and muscles, all were studied in detail through many shuttle flights and most effectively on the SpaceLab Life Sciences flights.

Some of the close calls that happened in the early shuttle days have still not been widely discussed. But coping mechanisms, drug therapies, exercise protocols, and other means to control or reverse some of the physiological affects of zero gravity have been honed to a high degree. Work continues on the International Space Station with long duration solutions as the goal.

We have found out a lot about the human body in space. It is remarkably adaptable. But there are limits and countermeasures must be applied and refined.

Much of this work has application to medicine here on earth. Many of the processes that accelerate in zero gravity are like the affects of aging. Countermeasures for zero gravity can find some applications with older folks here on the ground.

Scientific journals are full of this stuff, yet it is so technical and the jargon so dense, these extraordinary findings are largely ignored by the media and thus by the general population. In medical improvements for human life alone, the space program has more than paid for itself.

Next week I am on travel and we’ll see if I can continue this blog remotely! If not, the problem won’t be with the internet but with the operator (me!). See you then, I hope.