Mars Is Within Reach
By Dr. Robert Zubrin, American Thinker, 12.27.16
On November 28, a syndicated op-ed by Charles Wohlforth and Amanda Hendrix appeared in the Los Angeles Times and carried over the following days by a number of other newspapers claiming that journeys to Mars are just a dream. According to these writers, the race to Mars “can’t be won with either’s [NASA’s or SpaceX’s] current technology, regardless of their spending or commitment. The barrier is human biology. Even a short sortie mission to Mars would be extremely hazardous to human health. A Mars colony is out of the question.”
These pessimistic pronouncements have no scientific basis. For example, while Wohlforth and Hendrix point to a UC Irvine study in which irradiated mice sustained brain damage, they failed to note that the mice in question received their dose at about 40,000 times the rate it would be experienced by astronauts on a journey to Mars. This discrepancy makes the study invalid. In toxicology dose rates are critical. A glass of wine a night will cause no ill effects; 40,000 glasses of wine drunk at once would unquestionably be fatal.
In fact, not only do the cosmic ray alarmists lack foundation for their claims, we have direct contrary evidence. As a result of extensive stays on board the International Space Station or Mir, about a dozen astronauts and cosmonauts have already experienced cosmic day doses comparable to a Mars journey, and there have been no radiological casualties. This is not surprising, since, on the basis of extensive radiation health knowledge, the radiation doses and dose rates involved pose no threat whatsoever of short-term effects, and at most about a 1 percent increase in statistical risk of contracting cancer at sometime later in life.
The authors are on somewhat firmer ground when they talk about the dangers of extended exposure to zero gravity, as there have in fact been harmful effects, including thinning of bones and weakening of muscles, observed. However, it must be noted that literally scores of astronauts and cosmonauts taking six-month tours (an equal duration to that required for flight from Earth to Mars using current propulsion) have survived such exposures. Moreover, a countermeasure -- artificial gravity produced by spinning the spacecraft -- that would eliminate all such effects is readily available.
To read the full article, please click here.
Dr. Robert Zubrin is President of the Mars Society and Pioneer Astronautics and author of The Case for Mars: The Plan to Settle the Red Planet and Why We Must.
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