Health and physiological effects of long-term human space travel

Human Space Travel: Environmental and Health Effects

Ever since people first looked up at the stars, mankind has wondered about going into space. What was up there? What would it be like? Was there life, looking back at them? Some of these questions have been answered by NASA and the space program, and some of the questions remain. However, it is no secret that space travel has effects on the human body and on the environment, and those are two areas that are not often discussed as thoroughly. In addition, there are financial costs (and the potential for big profits) to consider when it comes to space travel and human beings..

Effects on Human Health

One of the main effects on human health is on the cardiovascular system. Because there is little gravity in space, the fluids in the body are able to shift more easily, and that can result in a stuffy nose, puffy face, and headache (Effect, n.d.). Bones and muscles weaken more rapidly in space, as well, and the red blood cells in the body change their shape. Fortunately, the shape of the cells is easily reversible with a return to normal gravity. However, the weakening of the bones and muscles is not something that will simply correct itself when a space traveler returns to earth (Effect, n.d.). Anyone who travels in space should also be prepared for some motion sickness and a higher dose of radiation than the one to which he or she would normally be exposed on earth.

All of those things can cause short- and long-term problems for human health, and are worth carefully considering to make sure that the benefits of traveling in space really do outweigh the costs and potential costs that could be faced at a later date. One study on the subject, done by Ickes (n.d.), indicated that there were serious risks to long-term space travel that included bone loss and an overabundance of radiation. The following graphs, reproduced from Long (2001), address issues with bone loss and radiation. The work done by Ickes (n.d.) on that same subject, indicate the seriousness of the problem for those who may be interested in long-term space travel, although the paper concludes that current technology would allow long-term space travel to be possible, but inefficient for the common traveler without improvements to technological advances and space craft.

Travel could consist of traveling in space for periods of time as a tourist, or traveling to a distant planet for any reason at all. The length of time one would spend in space is what is most important, not the reason for the travel or where in space the traveler was going. A loss of bone, however, is clearly apparent in astronauts at a much younger age and more rapid rate than what would be seen in the average adult population. (Source: Long, 2001).

The second graph indicates the measure of radiation a person would receive and compares a long-term mission to Mars with smaller space missions, nuclear reactor work, and standard background radiation that would be received by the majority of the people on the planet just from daily life (Source: Long, 2001).

Costs and Profits

So, what is the financial cost of space travel, and what do space tourism companies stand to gain? According to Ellis (2011), a "ballpark estimate" for space travel is between $100,000 and $2 million dollars. In the next few years, people with that level of money to spend may actually have the opportunity to become space tourists, and travel into space on a vacation. A handful of private citizens who are not astronauts have actually journeyed into space already, and a few hundred more have gone as high as 80,000 feet - the point at which one can see both the curve of the earth and the blackness of the surrounding space (Ellis, 2011). Several private companies, though, are currently working on ways to get people to the moon for vacation, so they can walk on it in the same way astronauts did just a few short years ago.

Google has even sponsored a contest for the first company that gets a spacecraft back to the moon - presumably in a tourism capacity. The prize for this achievement is $30 million (Ellis, 2011). Naturally, that level of profit is a huge incentive to get private companies to begin exploring ways to send people into space efficiently, economically, and safely. Quite likely, it will not be long before a company has managed to claim that prize, but raising the money to build and man a spacecraft is not cheap. Many companies are working to raise capital, and they are looking for new and better materials that will be lighter, safer, and lower priced so they can give tourists their first experiences of being sent into space. Companies are basically starting from scratch, though, because the U.S. is actually behind where it was when the first man walked on the moon (Kaku, 2009). The reason behind the decline is the closure of the space program and the way that the first space race (the one that put men on the moon) was actually quite ill-conceived (Kaku, 2009). Progress can be made, but it will take time and money - and those things are often in short supply.