ICAMSR - International Committee Against Mars Sample Return

PUTATIVE MARTIAN LIFE NO THREAT TO EARTH?
by Barry E. DiGregorio

Dr. Robert Zubrin's surprising and arrogant comments regarding planetary protection policy and back contamination issues in the July/August Planetary Report left me wondering if he had blown a gasket with his quest to put humans on Mars. He states in the article that anyone who believes that human Mars explorers could be infected by putative Martian organisms is not only "Illusory but hallucinatory". Is that a fact Dr. Zubrin? You better mention that to NASA's Planetary Protection Officer Dr. John Rummel because Rummel still seems to think there is a reason for his job.

Zubrin then cites that the return of Martian soil samples could not be harmful in anyway! He says "the kindest thing that can be said about this argument is that is just plain nuts". Obviously Zubrin is of the opinion that NASA's planetary protection program is a waste of time and money. While I can appreciate Dr. Zubrin's zeal and gung-ho-humans-to-Mars philosophy, he is out of his field with his comments on forward and back contamination. I find it incredibly amusing that Zubrin does not mention the recent Space Studies Board report titled "Preventing the Forward Contamination of Europa".

Spawned over the issue of whether or not to crash the Galileo spacecraft into Europa, great concern was expressed by a number of scientists (biologists) in this report who advocated avoiding the contamination of Europa with Earth microbes contained within the spacecraft. The Surveyor III lunar probe brought back to Earth by the Apollo 12 crew demonstrated the survival of Earth organisms for 2 1/2 years inside the probe. Given the unbelievably harsh conditions at Europa compared to Mars, one has to wonder why Robert Zubrin and others who share his "no-planetary-protection-policy-needed" philosophy do not have the same concerns for protecting Earth against Martian microbes as the Space Studies Board has for the Jovian moon Europa?

In 1981, NASA published a detailed study entitled "ORBITING QUARANTINE FACILITY: The Antaeus Report" (NASA SP-454). The purpose of the book is thus described:

"A design is presented for an earth-orbiting facility for the analysis of planetary return samples under conditions of maximum protection against contamination but minimal damage to the sample. The design is keyed to a Mars sample return mission profile, returning 1 kg of documented subsamples, to be analyzed in low earth orbit by a small crew aided by automated procedures, tissue culture and microassay. The facility itself would consist of Spacelab shells, formed into five modules of different sizes with purposes of power supply, habitation, supplies and waste storage, the linking of the facility, and both quarantine and investigation of the samples. Three barriers are envisioned to protect the biosphere from any putative extraterrestrial organisms: sealed biological containment cabinets within the Laboratory Module, the Laboratory Module itself, and the conditions of space surrounding the facility."

Clearly, this NASA report took a hard look at the issue of back contamination from Mars very seriously, to the point of building a special facility for that purpose in Earth orbit. Of course dwindling NASA support and funding virtually eliminated any possibility of constructing the Orbiting Quarantine Facility described in the book. However, since the time the NASA Antaeus Report was written, increasing evidence for life on Mars has been accumulating such as the recent discovery by Dr. Steven Benner of the University of Florida's Department of Chemistry. Benner published a paper in the PNAS journal citing the inability of the Viking GCMS to find organics on Mars in 1976. Benner says the GCMS could have missed organic matter he believes must be in the Martian soil from meteorites. He says any organic molecules derived from life processes could also have been missed. It was the Viking GCMS that was used by NASA in 1976 to render the verdict that no evidence for life had been found on Mars by the Viking biology instruments, even though they produced intriguing results. Viking Project scientist Gerald Soffen is often quoted as saying regarding the GCMS findings: "That's the ball game, no organics, no life". NASA then announced to the press that Viking found no evidence for life - a completely unjustified conclusion. Why? Because former Viking biology experimenter Dr. Gilbert Levin and his co-experimenter Dr. Patricia Ann Straat had said their data from Mars was consistent with a biological response. Dr. Benner's paper in PNAS is now supporting evidence of a flawed Viking GCMS.

More recently, Dr. Michael Malin and colleagues published a paper in Science in June of this year describing new evidence that Mars may have liquid water very near its surface today. This dramatically improves the likelihood of extant life on Mars.

Another key issue raised in the Antaeus Report is not even mentioned by Zubrin. Organisms taken from their natural environment and placed in a completely foreign environment not only out-competed indigenous organisms but also flourish. What if this scenario also happens with any organisms brought back from Mars? Surely, the possibility has to be considered. That is why we have a planetary protection program in the first place.

Dr. Zubrin accepts the notion of planetary exchange of debris, but uses this to conclude that Earth has already been inoculated against germs from Mars. Is this really a rational theory? Where is the supporting evidence to make a case to abandon planetary protection? Who is to say that such interplanetary infections have not been the cause of unexplained extinction’s of species on Earth in the past? Was disease also a culprit in the extinction of the dinosaurs. Many scientists now think so. The K-2 impact event 65 million years ago did not kill off the dinosaurs, they lived on another 2 million years. Also, Dr. Ross McPhee of the American Museum of Natural History has now postulated that a species crossing hyperdisease killed off the Pleistocene mammal’s 13,000 years ago. Are we so sure that interplanetary infection was not a cause? Dr.'s Chandra Wickramasinghe and Fred Hoyle from Cardiff University in England have correlated cometary tail debris with outbreaks of influenza on Earth. Shouldn’t we look into this sort of information more closely before returning samples from comets or planets considered to be possible habitats?

The horrific truth about microbes is that all they need is to find Earth-life to be a good source of food, and to have the capacity to harvest it. H. G. Wells' "War of the Worlds" had a favorable outcome, but Wells' invaders were not microorganisms, although his story ends with Earth microbes killing off the Aliens.

Even if Zubrin's assumptions are considered reasonable by some, his argument does not hold against different reasonable assumptions. When the entire biosphere hangs in the balance, it is adventuristic in the extreme to bring Martian life here, or send astronauts to Mars before we know the capabilities of any organisms that might exist there. Sure, there is a chance it would do no harm; but that is not the point. Unless you can rule out the chance that it might do harm, you should not embark on such a course before making absolutely certain.

Any rational benefit-risk study would find that any conceivable benefit pales before the risk-no matter how small-to our biosphere. Science must move in increments when dealing with hazardous unknowns. We should first send many more robotic probes to seek and characterize life, something we have barely begun. Only one mission ever searched for life on Mars -- that was Viking over 24 years ago and it returned positive signals! The Viking biology data should be a warning. The Beagle 2 exobiology lander may shed more light in 2003.

So while we are waiting for the issue of life on Mars to be settled, why not use our time wisely by developing new human space flight technologies and then practice them on Earth or the Moon for an eventual human mission to Mars? In this way, we do not have to risk any lives or our biosphere. When dealing with issues involving planetary protection we must have patience. Remember that old phrase "An once of prevention equals a pound of cure?" In exposing Earth to unknown risk, this is an enormous understatement.

Barry E. DiGregorio is the founder of the International Committee Against Mars Sample Return (ICAMSR) http://www.icamsr.org and author of Mars: The Living Planet.