This is a copy of my story from the HMS Beagle, a BIo MedNet magazine.
Mars or Bust
by Sibylle Hechtel
Posted October 15, 1999 · Issue 64
Highlights of the Second International Convention of the Mars Society include a debate on whether there is, or ever was, life on Mars; an overview of the new Mars Arctic Research Station; strategies and technologies for research in extreme and remote environments; the pros and cons of Mars research; and the relationship between Biosphere II and the possible settlement of Mars.
Cars sporting “Mars or Bust” and “Vulcan Academy” bumper stickers joined the usual throng of seventies hippies in their old Volkswagen vans and nineties yuppies in expensive new sports utility vehicles on the streets of Boulder, Colorado. The Second International Mars Society Convention, held August 12-15, 1999 at the University of Colorado, attracted visitors from around the world.
Celebrities including astronaut Buzz Aldrin and film director James Cameron (of Titanic fame) joined invited speakers from North and South America, Europe, and China. Robert Zubrin, president of the Mars Society and opening speaker, talked so fast and enthusiastically that he bounced up and down at the lectern. “John F. Kennedy said in 1962, ‘We choose to go to the moon. We choose to go not because it is easy, but because it is hard,’” Zubrin quoted, and continued, “By 1969, we were on the moon.” Thirty years later, we have not gotten much farther.
Was there life on Mars? Is there life on Mars? Will there be life on Mars? All questions were hotly debated. Zubrin said, “If we find life on Mars, it shows that life is likely to be everywhere.” In August 1996, Everett Gibson at NASA’s Johnson Space Center and his colleagues announced the discovery of possible fossils in ALH 84001, a 4.5-billion-year-old meteorite from Mars. It was the oldest rock ever obtained from Mars or any planet, including Earth.
The meteorite contained carbonate globules thought to have formed between 0 to 80 degrees Celsius; ovoids, which could be nanofossils, near the carbonate globules; polycyclic aromatic hydrocarbons; and magnetite chains. Magnetites are produced by bacteria on Earth and are very small, about 40 to 60 nanometers. ALH 84001 has chains of up to 25 magnetites, much like terrestrial bacteria. Gibson showed scanning electron micrographs (SEMs) of magnetites from both Earth bacteria and the Martian meteorite, which looked the same.
From SEM data, Gibson and his colleagues deduced the existence of biofilms, cocoon-like envelopes that bacteria secrete to make their habitat more livable. In terrestrial bacteria, biofilms provide a specific signature with recognizable morphology and composition. Gibson’s group found putative biofilm fossils that appear the same as terrestrial biofilms in three different meteorites, ALH 84001 and two others. Fossil biofilms similar to those in ALH 84001 have been found in two other meteorites. Core samples of Columbia River basalt contained living bacteria, identical to the nanofossils found in ALH 84001. Gibson and colleagues are also studying bacteria found in 11,000-foot-deep gold mines in South Africa.
Asked about life on Mars today, Gibson replied, “If it was ever there - and we have evidence that it was - then it’s still there today, surviving wherever there’s water, where it is protected.”
Chris McKay, of NASA’s Ames Research Center, agrees that there was once life on Mars. “Magnetite is the strongest meteorite evidence for life,” he said. But to McKay, whether there was life is the small question. The big question is, Was there a separate genesis on Mars?
Early Mars, at the time that it is thought to have had life, was warmer and had liquid water on its surface. Since then, the planet has lost its atmosphere and become much colder. One hypothesis to explain this is based on the fact that CO2 is unstable and forms CaCO3. On Earth, with plate tectonics, subduction plates take the CaCO3 into the interior where the heat in the core then releases the CO2 - a prime “greenhouse” gas that helps retain heat - back to the atmosphere.
Mars, because it is too small, has no plate tectonics and thus no CO2 recycling. The binding of atmospheric CO2 into CaCO3 may have led to the loss of Mars’ atmosphere and its consequent transformation into a cold, dry, dead planet. McKay thinks that no life survived. Greenland, he said, “has ice, energy, and nutrients - but no life. If there’s no life on Greenland, then we expect no life on Mars.”
On the other hand, Larry Kusnetz, at the University of California at Berkeley, thinks that liquid water could exist on Mars. The Viking lander, he said, “recorded areas of temperature and pressure adequate to have liquid water.”
While researchers disagreed as to whether life could exist on Mars today, they agreed that the best way to find out is a manned mission.
Pascal Lee and Charles Cockell, both from NASA Ames, gave an overview of the Mars Arctic Research Station (MARS), to be run by the NASA Ames Center for Mars Exploration. The MARS will be located in a meteor impact crater, about 20 kilometers across and 23 million years old, called Haughton Crater and located on remote Devon Island in Canada at 75° N latitude. One of its goals is to learn strategies and technologies for research in extreme and remote environments, such as the Martian surface. Carol Stoker, also at NASA Ames, considered it a practice habitat for Mars surface exploration.
There are seven meltwater lakes in Haughton Crater that are very low in organic compounds and are exposed to high levels of UV radiation. Cockell studied how organisms protect themselves from UV. One strategy of certain algae was to form a lift-off mat with brown scum on top. The mats grew on the lake bottom and then broke off and floated to the top. The brown scum contained scytonemin, an aromatic organic compound that absorbs UV radiation, distributed in a sheath around the cells. Other algae growing on rocks were covered with globules of non-protein amino acids that were UV protective.
“This gives us a clue for types of chemicals to look for on Mars,” said Cockell. The Martian surface is exposed to extremely high UV levels. Cockell described the Earth micro-oases he found, areas of a few square meters that contained unusual concentrations of plants and animals, islands among barren rocks. If we learn why these form, he suggested, “then perhaps we can create them on Mars, which is essentially a polar desert.”
Next, science fiction writer Kim Stanley Robinson - author of Red Mars, Green Mars, and Blue Mars, an award-winning trilogy about the exploration and colonization of the planet - reviewed some of the pros and cons of such an endeavor. Robinson favors going to study Mars or to search for life on Mars. But, he said, “If we find living bacteria, everything is put on hold - we wait to study the bacteria before settling Mars.” Comparative planetology would help us with Earth climatology, he continued. Robinson noted that the hole in Earth’s atmosphere was first found as a result of research on the Venusian atmosphere.
Abigail Alling then discussed her experience living and working in Biosphere II in relation to the possible settlement of Mars. In the Biosphere II project, eight people lived in an enclosed self-sustaining ecosystem for two years. After they entered the sealed system, oxygen levels fell from 21% to 14.2%, risking failure of the project. Careful search for the cause revealed that the cement from which the biosphere was constructed bound the oxygen.
Meanwhile, the 150 crops grown - selected from 1,500 tested - provided all the inhabitants’ food for two years. “Biospheres are not sustainable,” said John Allen, founder of Biosphere II. “They produce a surplus.”
Mark van Thillo, a Belgian member, stressed the importance of redundancy to the Biosphere operation (and an eventual Mars base). There were sufficient air pumps that if they lost 50% capacity they could maintain the air conditioning. Rainwater valves had automatic operation with manual backups. “Many lessons from Biosphere II are applicable to closed systems,” he concluded. Alling put it more strongly, “People who want to go to Mars should to through a Biosphere-type stay first, where they are locked in, to test their ability to tolerate a closed environment.”
Sibylle Hechtel is a freelance writer whose articles’ topics include science and rock climbing.
Andrzej Krauze is an illustrator, poster maker, cartoonist, and painter who illustrates regularly for HMS Beagle, The Guardian, The Sunday Telegraph, Bookseller, and New Statesman.
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Dating of Meteorite Mineral Leaves Mars-Life Hypothesis Alive - the ancient age of the famous Allan Hills 84001 meteorite is confirmed.
On the Question of the Mars Meteorite - an informative site from NASA’s Lunar and Planetary Institute, with commentaries on recent papers and other meteorite news.
An Exobiological Strategy for Mars Exploration - a detailed 1995 report prepared by NASA’s Exobiology Program Office.
Mars Exploration Program - contains science information, maps, and pictures from the Mars missions. From NASA’s Jet Propulsion Laboratory.
Biosphere 2 Center - maintains extensive research information from this ongoing experiment. From Columbia University.
Bringing Life to Mars and The Future of Space Exploration - discusses the potential for future life on and exploration of Mars. From the March 1999 special issue of Scientific American.
Beagle 2: A British Lander for Mars - the Mars expedition will share its name with this publication. From Mars Society’s New Mars journal.
Astrobiology: Formulating the Big Picture - HMS Beagle Opinion on the future of the field of astrobiology.