Health in Space By Jewel Davis

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    “Unbearable Lightness” and “Environmental Health in Space” are two scientific articles that addrress the harmful effects of space travel on the human body.  The articles mainly focus on the effects of weightlessness in space. Weightlessness is the cause of many problems astronauts experience in space. Some of the problems that occur in space due to weightlessness are motion sickness, weakening of the muscles and bone loss. Scientists are now experimenting with new ideas and simulations to find ways to counteract the effect on the body due to the lack of gravity.  Hyper gravity and the usage of centrifuges are a few possible ways to improve the ailments caused in space.

    Weightlessness is “a medical nightmare of gigantic proportions” because it causes many problems in the human body. Members of space crews spend months in space without the “grounding force of gravity” exposed to every element in space (Wright 1). Motion sickness occurs the first couple days in space “when signals from the eyes conflict with confused messages from the inner ear and other gravity-sensing organs” (Wright 1). Blood and other fluids shift to the chest and face due to “a loss of hydrostatic pressure” (Hamaoka 1). Since there is no gravitational pull, the heart muscles don’t pump as hard so they begin to weaken (Wright 1). Blood volume is lost and there is a decrease in red blood cell mass (Hamaoka 1). Muscles that are used to stabilize the legs and spine become weaker as well (Wright 1). Without the presence of gravity, astronauts lose about 2% of their bone mass every month they are in space (Wright 1). The effects of weightlessness are very hazardous to space explorer’s health. In the four decades since human space flight began, scientists have struggled to understand the effects made on the body (Wright 1).rocket

    Many Scientists have attempted to come up with ways to fight the effects of weightlessness. Before going up into space, astronauts exercise up to two hours a day strapped to treadmills with bungee cords to strengthen their muscles for the flight. But, exercise only offers a little bit of protection against body deterioration (Wright 1). Astronauts who may be up in space for only a week or two need days of recovery before they can do normal things like running, driving, or even standing up without getting dizzy. Their weak bones take even more time to rebuild their strength (Wright 1). Scientist Malcolm Cohen of the NASA Research Center in Moffett Field describes it as a “person becoming more of a space creature than an Earth creature, it’s not so bad, as long as the person stays weightless. But then they have to come back to Earth” (Wright 1)

    Scientists believe the cure to all of these ailments could be hypergravity.  Hypergravity is “a force stronger than Earth’s gravitational field delivered to astronauts on a centrifuge”. A centrifuge is a machine that is comparable to a salad spinner . Its arm “turns horizontally from a central hub” (Wright 1). Astronauts lie on the centrifuge with their “head toward the pivot point, the outward pushing force translates into a downward push from the head toward the feet that challenges the heart, muscles, and bones much as standing on Earth does” (Wright 1). How fast the machine spins depends on how much force is wanted to be used (Wright 1). Humans can endure up to two to three g’s. G’s are the measurements of the gravitational pull on Earth (Wright 1). Scientists believe a few minutes of experiencing hypergravity in space might be able to make up for days of free floating (Wright). Scientist Charles Oman of the Massachusetts Institute of Technology stated that “the basic idea is to use short blasts of g to reverse some of the adaptations to weightlessness” (Wright 1).jump

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    Another counteraction to weightlessness is the usage of vibrations (Wright 2). Scientist Clinton Rubin of the State University of New York at Stony Brook found that high frequency vibrations may have the ability to strengthen bones (Wright 2). The vibrations trick the muscles into thinking they are active so they become stronger (Wright 2). The usage of bone building drugs might also help prevent bone loss during extended space travel. But, this isn’t as appealing as the centrifuge because it only focuses on one aspect of the body harmed in space (Wright 2). 
    For the past 40 years, we have extended our reach beyond earth’s physical boundaries into a distant foreign realm (Hamaoka 1). New discoveries that have been made in space have helped us learn more about the world around us and our own planet. Although only about 300 astronauts have experienced being up in space, it is an industry that grows more and more every day (Hamaoka 1). As more people begin to venture out in space, more people will experience weightlessness.  Not having the force of gravity is not as fun as many people believe it to be. Weightlessness is a dilemma that causes many problems while in space and back on earth.  An increasing number of scientists are looking for ways to make the transition from earth to space a more fluid process. Hypergravity may be a way to counteract the symptoms of weightlessness. But, only time and many hours of research will tell.


Works Cited

Hamaoka,Takafumi. “Environmental Health in Space.” Environmental Health Perspectives 109.7 (2001). EBSCO. UNC Lib., University of North Carolina. 29 Oct. 2004  <http://search.epnet.c om/login.aspx?direct=true&AuthType=cookie,ip,url,uid&db=afh&an=5230169>.

Wright, Karen. “An Unbearable Lightness.” Discover May 2003: 24.5 (2001). EBSCO. UNC Lib., University of North Carolina. 29 Oct. 2004 <http://search.epnet.com/login.aspx?direct=true&AuthType=cookie,ip,url,uid&db=afh&an=9474976>.

Image Source
All images came from NASA's GRIN (Great Images in Nasa) website

Related Links
Vanderbilt Center for Space Physiology and Medicine
Lost in Space: Bone Mass
National Space Biomedical Research Institute