Wednesday, March 16, 2005
Mars Colonies Coming Soon?
By John Roach
National Geographic News
As rovers and orbiters continue to scour Mars for more signs of water and the potential for extraterrestrial life, space scientists and enthusiasts are champing at the bit to put humans on the red planet.
In recent months, spacecraft roaming and orbiting Earth's closest neighbor have identified regions where large supplies of water may be accessible from the surface. They have also located areas where gases such as methane could support oxygen-producing bacterial life.
Such discoveries are raising the possibility that life lives on Mars today, did so in the past, and with the help of humans, could do so in the future. To find out for sure, space scientists and enthusiasts say humans need to travel to Mars.
"There's no question we'll ultimately go there. It's a matter of when, not if," said Lynn Rothschild, an astrobiologist at the NASA Ames Research Center in Moffett Field, California. (Astrobiology is a branch of biology that searches for extraterrestrial life-forms.)
Robert Zubrin is the president of the Mars Society, a Colorado-based organization that promotes human exploration and settlement of the red planet. He said the technology exists to put humans on Mars within a decade.
"We are much closer to being able to send humans to Mars today than we were to being able to send men to the moon in 1961, when [United States President John F. Kennedy] started the Apollo program," Zubrin said.
Under the leadership of Kennedy, humans first set foot on the moon July 20, 1969. Given similar visionary leadership, Zubrin said, humans can walk on Mars within the decade and begin the process of colonization.
The surface temperature of Mars is –81° Fahrenheit (–63° Celsius). The planet is bombarded by ultraviolet radiation, and its atmosphere is about 95 percent carbon dioxide.
While such conditions are less than ideal for Earthlings, there's "nothing about Mars today except [ultraviolet] radiation on the surface that would preclude life from surviving there," Rothschild, the NASA astrobiologist, said.
Any life would need to be shielded from the high levels of ultraviolet radiation on the surface and presumed oxidants, she added.
Rothschild noted that surviving is different from thriving, multiplying, and spreading. For humans to thrive on Mars and to have a continued presence there, they will need to transform the atmosphere and climate to suit human needs: The atmosphere needs to be full of breathable oxygen and the climate warm enough for liquid water.
Many scientists believe that billions of years ago, Mars was a warm, wet place. Such conditions may have been more hospitable to life. Scientists also believe that the red planet can be transformed to support life again, including human colonies.
The process of transforming a planet to make it hospitable for humans is known as terraforming. NASA scientists, groups such as the Mars Society, and Internet-based communities such as Red Colony continually discuss how to colonize and terraform Mars.
While no single method or process is considered best, Rothschild said the common goal is breathable air and drinkable water. "If you get oxygen and liquid water, you can do a whole lot," she said.
Rothschild's major concern about human exploration of Mars is that the mere presence of humans will contaminate the planet and potentially compromise any life that may be there.
"If you're trying to look for indigenous life and you contaminate the area, it will be difficult to prove it's not just something you brought along with you," she said.
Zubrin said not to worry. Modern biological techniques allow scientists to determine the genetic identity of any microorganism.
By way of example, Zubrin pointed to the anthrax attacks in Washington, D.C., and New York City in the fall of 2001. "Scientists were able to determine that the microbes in question were not only anthrax, but that the anthrax stock in question originated from a lab in Ames, Iowa and, furthermore, that the [anthrax] had been taken from the Ames lab in 1987," he said.
Zubrin said scientists, using similar techniques, could determine if microbes potentially found on Mars are from a space-launch site on Earth, from material ejected during an asteroid impact millions of years ago, or truly Martian life-forms.
Rothschild, meanwhile, pointed out the potential political risks of endorsing Mars colonization. She said human lives may be lost during trips to Mars and few politicians have the will to allow astronauts to die under their watch.
"But there are plenty of people who are willing to take that risk," she said. "There are people who will take a one-way ticket to Mars. There are plenty of volunteers."