Space travel: Can the human body handle the long journey to Mars?

  • 8 years ago
MARS — In a recent opinion article on CNN.com, U.S. President Barack Obama stressed his goal of not only sending humans to Mars, but making it possible for extended stay by 2030.

Obama praised NASA for building the groundwork in American space travel and lauded the private sector, which has grown exponentially in the past few years. He also announced that the government is working with commercial partners to make it possible to travel to and stay on Mars.

But the journey alone won’t be an easy one. From what scientists already know about space travel, it can have harmful effects on the human body.

According to James A. Pawelczyk, Ph.D. — an physiology and kinesiology researcher, who served as a payload specialist aboard the space shuttle Columbia in 1998 — one of the dangers of space travel is exposure to radiation.

In a 2005 article written for Penn State’s website, Pawelczyk described solar rays passing through metal as something akin to rain passing through chicken wire. Without the protection of Earth’s atmosphere, humans are vulnerable to the sun’s gamma rays and hot neutrons, which can cause cancer.

There are two ways to deal with solar radiation during space travel. The first is to create a shield to absorb the radiation and protect the human body.

Pawelczyk noticed on the Russian space station Mir, astronauts slept with their heads near large lead batteries to shield themselves from the rays. Lead is a great absorber of gamma radiation. Another excellent shield is water, according to Pawelczyk, for its high hydrogen concentration. Water in its densest form, ice, provides even more absorption of gamma rays. And the thicker the shield, the better the absorption and protection.
Another alternative to avoiding radiation is to decrease the amount of time spent in space. In other words, finding a quicker form of transportation.

During space travel, humans are also prone to osteoporosis. Astronauts in space have been recorded losing one to two percent of bone mass per month. During a round trip to Mars, which takes about a year, 10 to 25 percent of skeletal mass could be lost. Pawelczyk equates this to being bedridden for about 10 to 15 years.

On Mars, after months and months without gravity, space traveler’s bones and muscles may not be able to support their own body weight on Earth. While exercise aboard spacecrafts might help retain muscle and bone mass, astronauts have suffered massive loss.

Space causes other complications as well, including alterations to the circulatory system and the immune system.

Once on Mars, people will battle with lower temperatures. As Mars is farther away from the sun than Earth, the average temperature is about minus 80 degrees Fahrenheit, and can vary from minus 195 degrees F near the poles during the winter to as much as 70 degrees F at midday near the equator.

Mars’ thin and low pressure atmosphere also means little oxygen and very dusty conditions. The atmosphere of Mars is about 100 times thinner than Earth’s and is 95percent carbon dioxide. Furthermore, without adequate protection, Mars’ low pressure atmosphere would cause, skin and organs to rupture within minutes, leading to a quick and painful death.

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