Sunday, October 4, 2009

A one-way ticket to Mars? You first!

Physicist Lawrence M. Krauss recently suggested, in The New York Times, that one way to cut the costs of a manned mission to Mars was to make it a one-way trip for the astronauts. After all, Krauss reasons, the original American colonists didn't expect to return to England. Krauss claims that, heartless as his proposal may sound (really, you think?), informal polls among scientists encountered in his travels show that the majority would be happy to go to Mars with no thought of return.

Which only goes to show how extraordinarily intelligent people sometimes seem to lack the sense to come in out of the rain. Krauss is at least properly skeptical of claims that human space exploration is justified by humans being able to conduct scientific experiments better than robots, which is probably not true. His reasoning is that we need to establish ongoing human life on Mars in case something catastrophic happens to our native planet. Considering the almost insane challenges of the Martian environment for human life, Krauss's purposes would be nearly as well served by a proposal to colonize the submerged parts of the continental shelves of Earth's various land masses.

No one should doubt the invaluable additions to knowledge of properly conducted scientific research on Mars. Its age is similar to that of Earth, and it is the most earth-like planet in our Solar System, though the two planets' respective outcomes have been radically different. Whether liquid water exists far beneath its surface and, even more intriguing, whether biological life exists in some primitive form on Mars are important issues for understanding our own planet's history.

But not the issue here. No human could survive unaided on Mars's surface for 10 seconds. Because its atmosphere is of a thinness to be found at altitudes 19 times that of Denver, liquids boil and evaporate very quickly; a human's blood would boil inside him in seconds. Mars's temperatures are generally worse than those on Antarctica, while its thin atmosphere leaves the surface more vulnerable to the Sun's radiation than the hottest parts of the Sahara. Its atmosphere is 95% carbon dioxide, and it is plagued by storms of red dust lasting months at a time and capable of raising dust clouds 25 miles high.

No, the original American colonists did not expect to return to England, but they did expect to hunt, fish, and farm. Mars is not a candidate for any of those things. Indeed, the very need to protect astronauts from the radiation they are likely to encounter simply getting to Mars in the first place (the shortest possible trip would take 7–8 months) might make their transport craft too heavy to make the trip at all! Krauss acknowledges the issue, supposing a crop of astronauts arriving on Mars with their life expectancies radically cut short by radiation exposure. A promising start for establishing human life on the red planet!

Of course we have, or can develop, the technology to create habitable environments on Mars, perhaps beneath the surface. Let's suppose that, to prepare for such an eventuality, NASA constructs an artificial habitat somewhere on Earth and confines a group of male and female scientists there for some months. There is no TV, radio, or internet, and no real-time communication with the rest of humanity, only data links twice a day, as has been the case with the Mars Rover. One can't go outside without heavy protective equipment, and one may not be able to go outside for months at a time, because of the fierce dust storms, raging at speeds of hundreds of kilometers per hour. Oxygen and water must be manufactured, and attempts must be made to begin cultivating edible plants inside. No health care is available except for what can be provided right there. And these conditions will never change because of the very nature of the environment itself.

I suspect the eventual human result would include murder, insanity, sexual slavery, and rationing of food, water, oxygen, and medical care by some dominant personality and his clique to enforce his will on the rest of the group.

But supposing that didn't happen—that humans somehow learned to adapt and coexist in a civilized way completely inside an artificial environment, forever—Mars has two remaining disadvantages. Since it has so little atmosphere, it is much more vulnerable to meteor strikes than Earth, whose atmosphere burns up many of the debris from space that would otherwise wreak havoc here. Finally, Mars is a great deal smaller than Earth, so its likely future as a human outpost must be quite limited.

And lest we forget, in the light of what we know of evolution, the isolation of two previously compatible groups from the same species generally results in each group eventually developing characteristics so different that they can no longer mate and reproduce with members of the other group. The facts of biology tell us that unless we dispatched additional colonies to Mars at regular intervals to add to its human population, there would eventually come a time when the two groups would be of no further use to each other for propagating common descendants.

We are still too haunted by the ghost of Star Trek, which showed humans boldly going, not only to places where man had never been before, but where he simply can't go, unless we discover usable shortcuts through space-time. Mars, the one planet in our Solar System where humans might have even a remote chance of establishing an outpost, has the disadvantages described above. The closest possibility of another Earth-like planet lies in the vicinity of Alpha Centauri, 4.37 light-years from Earth. Light travels 5.8 trillion miles in a single year; at our current 18,000-mile-per-hour speed of space travel, it would take 37,200 years to travel the extent of a single light-year. Which reminds me of a joke by Johnny Carson. "The space shuttle is under warranty...120,000 miles or ten seconds." I think the late lamented king of late-night television had more common sense about this issue than our physicist friend Krauss. In the dawning age of robotics, there is no more reason to send humans to Mars or any other inhospitable environment than there is to station some hapless soul 11,000 miles above the Earth's surface on a GPS satellite to make sure motorists here below can continue to find their way.

© Michael Huggins, 2009. All rights reserved.

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