We often hear scientists and engineers working in the space industry make grandiose statements like, “We are a race of explorers. It is our destiny to travel to the stars.” They compare the courageous achievements of astronauts to those of Christopher Columbus and Magellan.
These high-sounding pronouncements strike a chord. People like to think of themselves in heroic terms.
Science fiction movies encourage this romanticism—alien creatures that look only slightly different from humans and space travel that seems safe and routine—even comfortable. Informed by this imagery, the general public has little appreciation for the formidable dangers and challenges of space travel.
The first movie to portray outer space as hostile to human life was "Alien" (1979) and its sequels. It portrayed an intelligent life form that was an encounter of the worst kind.
Recently there have been a few of what I call “near-future” sci-fi flicks that even more realistically portray the dangers of venturing into outer space. The most celebrated is “Gravity” (2013), starring George Clooney and Sandra Bullock, which won several Academy Awards.
Also in this genre are “Race to Mars” (2007), a Canadian feature, and "Europa Report" (2013). Both portray the dangers of space travel realistically. The drama intensifies as the vulnerable astronauts deal with a variety of life-threatening situations.
But even the most scientifically realistic documentaries and movies fail to account for all the dangers.
For example, two types of radiation threaten humans traveling in space. The Earth’s atmosphere and magnetic field shield nearly all solar and cosmic radiation. In space, however, the protection has to come from the spacecraft. Radiation from the sun, high-energy high-speed hydrogen protons, is dangerous but not nearly as devastating as cosmic radiation, which comes from distant exploded stars.
These consist of high-speed high-energy heavy particles. A recent study examined the potential for cosmic radiation to cause brain damage. It concluded: “Because iron particles pack a bigger wallop it is extremely difficult from an engineering perspective to effectively shield against them. One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.” They quickly add that it would be impossible to launch a spacecraft protected by this kind of shielding.
And people who promote colonizing Mars and even “terraforming” Mars never mention the effect of low gravity on muscle loss and bone loss. Mars gravity is only 38% that of Earth. Our bodies evolved to thrive in Earth gravity. Mars gravity wouldn't give humans the stress needed to maintain bone and muscle health. To date, this issue has been not been sufficiently researched, and so no practical solutions have been found.
With both spacecraft and meteorite fragments traveling at high speed, an impact can easily puncture the hull—a catastrophic event. In space, there is no air, so there is no air pressure. Temperatures approach absolute zero. This isn't anything like the voyages of Christopher Columbus, which required great courage and stamina. Conditions on these early voyages were austere, but the explorers enjoyed plenty of fresh food, water and air; ideal gravity, air pressure and temperature range; and protection from solar and cosmic radiation; In other words, they voyaged in the environment our species was born to thrive in.
We weren't born to thrive—or even to survive—in outer space or on the surface of another planet.
In my opinion, we need more information and less romance. We need to learn about the challenges and dangers, because they’re going to come with a high price tag. And you know who will pay for them. That’s right—you and me. So if these missions are to be attempted, and whether they succeed or fail, there better be a damn good reason to pursue them. Not some bombastic sentiment like, “It’s our destiny.”
Post by Dennis E. Coates, Ph.D., Copyright 2014. Building Personal Strength .
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