The dimensions and the consequences of
NASA’s quest for life in space
“Bacteria (single celled microbes) are the dominant form of life on the planet (Earth). There are ten times as many bacterial cells on our skin and in our large intestine as (the total number of) cells in our own body. We are nothing but a source of sustenance for bacteria.”
H. L. Smith: Department of Mathematics and Statistics, Arizona State University, Tempe, AZ
(Note: the brain alone has 86 billion cells.)
“The mathematics of uncontrolled growth are (is) frightening. A single cell of the single cell bacterium E. coli would, under ideal circumstances, divide every twenty minutes. That is not particularly disturbing until you think about it, but the fact is that bacteria multiply geometrically: one becomes two, two become four, four become eight, and so on. In this way it can be shown that in a single day, one cell of E. coli could produce a super-colony equal in size and weight to the entire planet Earth."
Michael Crichton (1969) The Andromeda Strain, Dell, N.Y. p247
(Note: He meant bacteria multiply exponentially and new calculations suggest it would take about two days for E coli to cover the Earth.)
The truth is that no one who speaks with authority about life on Earth, and certainly no one who speaks about life on Mars or in the rest of space: no one knows enough facts to make an unqualified statement that you could call truth about the dimensions of universal life. The only thing we know for certain is that robust microbes exist everywhere on Earth and they have murdered billions of humans here on Earth and kill thousands every day. And no one knows the potential consequences of interaction with alien microbes. Yet our space program is dead set on finding them and bringing them back to Earth.
Life in space a statistical certainty
The recent decision by the NASA Administrator to announce Universal Life is the result of a numbers game; a set of circumstantial evidence underlined by probability theory and sustained by statistics that have been augmented over time by new research, increasing evidence, new technology and new players who cannot even remember when all of science was absolutely certain that the Milky Way galaxy made up the entire universe.
The dimensions of that error are almost impossible to calculate. Recently astronomers with a small telescope in the clear air at the South Pole peeked at one tiny old section of our universe and found 800 trillion suns, some that are 7 billion light years away from our Milky Way spiral galaxy, which is one of trillions of galaxies that comprise the actual universe in which we live.
The numbers are overwhelming. And so on July 24, 2014, no less a scientist than Charles Bolden, the head of the National Aeronautics and Space Administration, told a public conference in Washington that there must be life beyond Earth. He said it flat out and without reservations, based on the security of vast numbers.
“It’s highly improbable in the limitless vastness of the universe that we humans stand alone,” the head of NASA said. And it didn’t make the front pages.
At that same meeting NASA astronomer Kevin Hand added, “I think in the next 20 years we will find out we are not alone in the universe.”
"Sometime in the near future, people will be able to point to a star and say, 'that star has a planet like Earth'," Sara Seager, professor of planetary science and physics at the Massachusetts Institute of Technology added. "Astronomers think it is very likely that every single star in our Milky Way galaxy has at least one planet."
Based on those predictions, NASA is asserting that there could be 100 million planets within our galaxy alone that could host life as we know it.
"What we didn't know five years ago is that perhaps 10 to 20 percent of stars around us (in the Milky Way Galaxy) have Earth-size planets in the habitable zone," added MattMountain, director and Webb telescope scientist at the Space Telescope Science Institute in Baltimore. "It's within our grasp to pull off a discovery that will change the world forever.”
What would prompt the normally conservative NASA leaders to jump so far off the ledge they have avoided so long? Numbers, and the ever-increasing numerical possibility of a confrontation with exobiology: tiny little life forms that have survived since time was young and adapted and learned to live upon the most basic energy sources available. The numbers tell us they must be out there, some closer than many of us realize. And moons are being added slowly to the long list of lively addresses.
In 2005 the European Space Agency’s Cassini space probe began studying Saturn, then its dozens of moons. Although neglected for years, a chance sighting of volcanic plumes on the moon Enceladus turned researchers’ attention to the tiny, icy satellite. Over the years Cassini made more than 17 passes through the plumes that turned out to be water ice jets.
Amazed by water ice jets and interested in their origin, the Cassini Equinox mission was redesigned to make low passes over Enceladus in 2008 and 2009. Using an instrument called a plasma spectrometer, elements in the plumes including gas and dust could be measured and identified. In 2010 the results of the analysis were completed and reported with a whisper. The space probe collected evidence for shirt-lived, negatively charged water ions and negatively charged hydrocarbons. (Negatively charged water ions can be found in familiar places on the surface of Earth, near waterfalls and breaking ocean waves for example.) Due to the presence of the negative ions in Enceladus’ plumes, the Cassini scientists said, there appears to be ongoing processes that could provide a suitable environment for life to evolve under the surface of ice.
Cassini's instruments also detected carbon, hydrogen, oxygen, nitrogen, and various hydrocarbons in the plumes. In 2009, the spacecraft's cosmic dust analyzer found sodium and potassium salts together with carbonates locked in the plumes' icy particles, strengthening the hypothesis that Enceladus hosts a subterranean ocean that may be similar to salt water. Enceladus, as it turns out, offers every condition necessary for life as we know it.
“While it’s no surprise that there is water there, these short-lived ions are extra evidence for sub-surface water and where there’s water, carbon and energy, some of the major ingredients for life are present,” said Andrew Coates from University College London’s Mullard Space Science Laboratory.
With so much data available and the power of computing on the cloud, we wonder why NASA cannot work backward from the icy mist to reckon what life forms might have splayed the Encaladus hydrocarbons.
Look, but don’t spend the price of touching
NASA is already planning to go to an asteroid and bring back some alien microbes, if it can. And it has complex and very expensive plans to send rocket robots to Mars to gather Martian microbes, if they are there, and bring them back to Earth. It is the next big mission on the NASA time line, as inevitable as Gemini and Apollo and Viking, unless the money is diverted to safer, less expensive missions to launch more super telescopes like the Kepler and the Spitzer Space telescopes that look but don’t touch.
One team longs for landings and samples. The other wants NASA resources and effort directed to the launch of the Transiting Exoplanet Surveying Satellite (TESS) in 2017, the James Webb Space Telescope (Webb Telescope) in 2018, and perhaps the proposed Wide Field Infrared Survey Telescope - Astrophysics Focused Telescope Assets (WFIRST-AFTA) early in the next decade.
Instead of looking for microbe exobiology these upcoming telescopes will find and characterize large things including new exoplanets -- those planets that orbit other stars -- searching for oceans and water signs in the form of atmospheric water vapor and for life as indicated by carbon dioxide, methane and other atmospheric chemicals. But they could discover more.
Life above the microbial level: Carl Sagan called them Macrobes
Just a month before the July Washington revelation, on June 9, 2014, Cornell University reported that there are 100 million places in the Milky Way galaxy that could support complex life, according to new research by its astronomers. They have developed a new computation method to examine data from planets orbiting other stars in the universe, the statement said.
Their study provides the first quantitative estimate of the number of worlds in our galaxy that could harbor life above the microbial level, they said. That escalation from microbes to “above the microbial level” is important beyond imagining, but not for the near future.
"This study does not indicate that complex life exists on that many planets. We're saying that there are planetary conditions that could support it. Origin of life questions are not addressed -- only the conditions to support life," according to the paper's authors Alberto Fairén, Cornell research associate; Louis Irwin, University of Texas at El Paso (lead author); Abel Méndez, University of Puerto Rico at Arecibo; and Dirk Schulze-Makuch, Washington State University.
The key phrases in all of this discussion are “origin of life questions,” and “chemical evolution” and “life as we know it.”
NASA’s Viking landers went to Mars in 1976 looking for life “as we know it,” without a solid idea of the extant variety of microbial life on Earth or its robust potential. Viking’s Labeled Release experiment nevertheless offered basic food stuff – all foods are chemicals- to Mars dirt with a seasoning of radiation to trace any reaction. It waited a while for digestion to take place Then it sampled the atmosphere in the sealed container. There, as predicted, meaningful levels of the decomposed food with a radioactive signature were detected as a gas by a simple beta radiation counter. As a control, the experiment, called Gulliver, over-heated a duplicate sample, tested it and saw no response – dead. Then, as any important experiment should be, it was repeated - successfully. Whatever was in the Mars dirt ate nutrients and gave off a signature of radioactive gas. Case closed.
Dr. Gerald Soffen, the chief Viking scientist said at the time in an interview with the author that NASA should concede Gulliver found evidence of life on Mars, but would wait for the discovery of water on Mars and carbon and other elements necessary for life as we know it to say Gulliver found proof of life on Mars. While water was discovered during his lifetime, organics were not clearly identified until December of 2014.
He admitted, however, “I think none of us have really come to grips with the ultimate question of what do we mean by life. What do we really mean by life? What is it you are looking for in the first place? It is as though you are saying we will know it when we see it but we are not sure what we are looking for. That is a very strange thing to say for somebody who has been hunting now for a long time. But I think the straightforward fact is that at this point in the 20th century (1976) we probably don’t know what life is.”
Life as we know it
In 2010, research conducted by biochemist Dr. Felisa Wolfe-Simon, then working for the U.S. Geological Survey, challenged the foundations of life as we know it. After a two-year study involving bacteria extracted from the mud of California's Mono Lake, near Yosemite National Park, Wolfe-Simon first reported in Science that the microbe, GFAJ-1, will grow in the presence of the toxic chemical arsenic, substituting it for phosphorous in its DNA when only slight traces of phosphorous are present.
Molecular biologist Steven Benner, who is part of NASA's "Team Titan" and an expert on astrobiology said at the time the organism at Mono Lake grew without high levels of the essential nutrient phosphate (although some phosphates were still present). While bacteria have been found in hellish environments on Earth and others have been found that can consume what other life finds poisonous, this bacterial strain has actually taken arsenic on board in its cellular machinery to use it in place of phosphorus, a molecule with properties similar to arsenic, he said.
Arsenic is poisonous to nearly all forms of life on Earth. Even small amounts of the poison become embedded in living tissue, causing renal failure and ultimately death -- in nearly everything but these bacteria. The bacteria were found as part of a relatively new hunt on Earth for life forms radically different from life as we know it.
Since the GFAJ-1 paper was published further research has concluded that the underlying, life-changing assertion that the microbe substituted arsenic for phosphorus is probably not correct. Yes the microbe GFAJ-1 survived in a world dominated by arsenic where very little phosphorus was present. No, there is no solid evidence so far that the microbe found a way to replace the phosphorus it needed to assemble its DNA with the similar scaffolding available in otherwise lethal arsenic.
William Bains is a British biotech researcher. He offered this insight in the January 2014 edition of Chemistry World:
“GFAJ-1 illustrates the problem that any trembling PhD student entering their viva will know. The scientist is an expert on their experiments, but they do not necessarily know the broader scientific context, or what standards of proof are expected of them. This situation is amplified when work bridges fields: a narrow, detailed training in one area does not give a deep understanding of the nature of evidence in another. Proof for a chemist requires different data and arguments than proof for a physicist. Neither is ‘better’: each is suited to the theory and understanding of its respective domain. The problems arise when geochemists try to make breakthroughs in biochemistry, biochemists in physics and so on. Obvious, perhaps, but in multidisciplinary research it becomes a major problem,” he wrote.
He added, “For the geochemists and physicists who wrote and reviewed the (GFAJ-1) paper, the idea that arsenic could substitute for phosphorus is unexceptional. It happens all the time in geology – why not DNA as well as rocks?”
Bains suggests science begins to lose its edge when the research involves team members from different disciplines. “Of course, all new science is multidisciplinary and always has been. And a rising tide of reports suggests that the scientific community is not just struggling to identify what is good science in nascent, niche fields like astrobiology, but in mainstream subjects.”
Paul Davies, the Arizona State University and NASA Astrobiology Institute researcher who co-authored the GFAJ-1 paper confessed at the time, "At the moment we have no idea if life is just a freak, bizarre accident which is confined to Earth or whether it is a natural part of a fundamentally biofriendly universe in which life pops up wherever there are Earth-like conditions."
Life pops up?
The idea that “life pops up” as a result of inevitable chemical evolution is the heart (if not the soul) of the search for alien life on Earth and beyond. And the creation and evolution of that study – exobiology - is the central theme of the science history book Inside NASA’s quest foe life in space. Today the concept that the chemical evolution of non-life can result in the emergence of something living is so fundamental that “understanding the process of chemical evolution or the origin of life,” is the base line standard goal for astrobiological missions to Mars and beyond. Creation is considered hokum. Life began when special chemicals were charged by some power source including volcanic heat or lightening, billions and billions of times over again until somehow molecules formed into living microbes.
The proposition was stated elegantly by George Wald back in 1955 when it first gained popularity. "The important point is that since the origin of life belongs in the category of at-least-once phenomena, time is on its side. However improbable we regard this event...given enough time it will almost certainly happen at least once... Time is in fact the hero of the plot. The time with which we have to deal is of the order of two billion years. What we regard as impossible on the basis of human experience is meaningless here. Given so much time, the 'impossible' becomes possible, the possible probable, and the probable virtually certain. One has only to wait: time itself performs miracles."
The dogma of inevitable chemical evolution constrains everything we do that involves the search for life in space. The manual the engineers and scientists must follow when building machines to search for life as we know it beyond Earth is a lecture in the most complex levels of reconciling engineering to the demands of sterilization, whether they are followed or not.
The Committee on Space Research (COSPAR) of the International Council for Science describes five categories of sterilization for interplanetary missions, and there are suggested ranges of planetary protection requirements for each category, the guidelines state:
• “Category I includes any mission to a target body that is not of direct interest for understanding the process of chemical evolution or the origin of life; no protection of such bodies is warranted, and no planetary protection requirements are imposed by COSPAR policy.
• Category II missions are missions whose target (heavenly) bodies are of significant interest relative to the process of chemical evolution and the origin of life but in which there is only a remote chance that contamination carried by a spacecraft could jeopardize future exploration. COSPAR requires only simple documentation that includes preparation of a short planetary protection plan in the form of an outline of intended or potential impact targets, brief pre- and post-launch analyses detailing impact strategies, and a post-encounter and end-of-mission report providing the location of impact, if such an event occurs.
• Category III missions (mostly flyby and orbiter missions) are missions to a target body of chemical evolution and/or origin-of-life interest or for which scientific opinion indicates that there is a significant chance of contamination that could jeopardize a future biological experiment. COSPAR requires documentation of planetary protection issues and some implementation of protection procedures that include at a minimum trajectory biasing, the use of clean rooms during spacecraft assembly and testing, and possibly spacecraft bio-burden reduction. An inventory of bulk constituent organics is required if the probability of impact is significant.
• Category IV missions (mostly probe and lander missions) target a body of chemical evolution and/or origin-of life-interest or for which scientific opinion indicates that there is a significant chance of contamination that could jeopardize future biological experiments. COSPAR requires detailed documentation of planetary protection issues, including a bioassay to enumerate spacecraft bio-burden, an analysis of the probability of contamination that may include trajectory biasing, use of clean rooms during spacecraft assembly, bio-load reduction, partial sterilization of any direct contact hardware, and a bio-shield for that hardware. The requirements and compliance are similar to those imposed for the Viking missions, with the exception of lander or probe sterilization.
Thus instead of Viking-style sterilization Curiosity was sterilized sufficient to prevent earth microbe interference with its experiments and ordered to stay away from newly declared “hot spots” on Mars where a nuclear accident might endanger the native bioata.
• Category V comprises all return-to-Earth missions, where the concern is the protection of the terrestrial system comprising the Earth and the Moon. The Moon must be protected from back-contamination to retain freedom from planetary protection requirements for Earth-Moon travel. For solar system bodies deemed by scientific opinion to have no indigenous life forms, an “unrestricted Earth return” subcategory is defined. Missions in this subcategory have planetary protection requirements on the outbound phase only that correspond to the category of that phase (typically category I or II). For all other category V missions, in a subcategory defined as “restricted Earth return,” the highest degree of concern is expressed by the absolute prohibition of destructive impact upon return, the need for containment throughout the return phase of all returned hardware which directly contacted the target body or unsterilized material from the body, and the need for containment of any unsterilized sample collected and returned to Earth.”
The standard that is expected to be in place for all microbe sample return missions is advocated by the European Science Foundation. It says, “The probability that a single unsterilized particle of 10 nanometers or greater in diameter is released into the Earth environment shall be less than 10 to the 6th power.”
According to the most recent NASA documents, “The ESF study confirmed that a probability of ‘1 in a million’ is a level of risk consistent with a range of other significant societal risks, and recommended that this level be accepted as the requirement for containment of particles of Martian material brought deliberately to Earth.”
While we are planning to dissect alien life once it is safely secured, the latest gathering of Mars experts is still foundering. On July 24, 2014 at the conclusion of Eighth International Conference on Mars the attendees agreed that scientists found themselves asking the same questions they had been chasing for decades.
“There’s a lot of knowledge and not so much understanding,” Phil Christensen, a Mars geologist at Arizona State University in Tempe told a reporter. “The devil continues to be in the details.”
NASA’s astrobiology cannon is based on the theory of chemical evolution as espoused first in the 1930’s and developed into the 1960’s. A groundswell of astronomical research suggested that the universe is filled with the same basic gases and elements that are key to life on Earth. Other research at the University of Chicago had found those same gases could be stimulated in a laboratory to form complex molecules similar to the molecules that are essential for the life in a cell.
Curiosity’s original mission to identify signs of ancient life was overruled and restricted because of its limited decontamination and radioactivity.. Curiosity’s operators were warned to avoid water and any place where extant life might be lurking. The one-year mission of the Curiosity Rover on Mars was limited to determining if the area around its landing site — Gale Crater — had ever been capable of supporting microbial life (as we know it.) “Yes,” the 1-ton rover said, absolutely YES; just seven months after touching down and after roving only a few hundred yards.
Curiosity’s Chemistry & Mineralogy (CheMin) and Sample Analysis at Mars (SAM) instruments found what NASA said were most of the chemical ingredients considered essential for life including sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon. The mix of compounds suggested that the area that was first examined in Gale Crater at Rocknest on Oct. 17, 2012 may have contained chemical energy sources for potential Mars microbes, the researchers said.
From October through June of 2013Curiosity was also sniffing for methane in the Gale Crater atmosphere, a sign of either microbe digestion or, less likely, geochemical activity. In September of 2013 NASA reported finding no signs of methane. According to NASA, Curiosity analyzed samples of the Martian atmosphere for methane six times from October 2012 through June and detected none. Given the sensitivity of the instrument used, the Tunable Laser Spectrometer, and not detecting the gas, scientists calculated the amount of methane in the Martian atmosphere must be no more than 1.3 parts per billion, which is about one-sixth as much as some earlier estimates.
Details of the findings were published in Science Express.
"It would have been exciting to find methane, but we have high confidence in our measurements, and the progress in expanding knowledge is what's really important," said the report's lead author, Chris Webster of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We measured repeatedly from Martian spring to late summer, but with no detection of methane."
NASA hoped to get this methane discussion resolved before the ExoMars mission arrived. The Europeans and Russians have staked a strong claim to this organic discovery. Concentrations of methane were recorded in 2003 and 2006 by their orbiter in three specific regions of Mars: Terra Sabae, Nili Fossae and Syrtis Major, and data suggest that water once flowed over these areas.
The ExoMars program co-operated by Russia and the European Space Agency is seeking further confirmation of the methane that the Planetary Fourier Spectrometer (PFS) onESA's Mars Express and the very high spectral resolution spectrometers on ground-based telescopes have detected in the atmosphere of Mars.
According to its publicists, the scientific objectives of the ExoMars program 2016-2018 include: searching for signs of past and present life on Mars, studying the water and geochemical environment as a function of depth in the shallow subsurface, and investigating Martian atmospheric trace gases and their sources.
To achieve these objectives, ESA’s ExoMars Trace Gas Orbiter, to be launched to Mars in 2016, will measure and map methane and other important trace gases with high sensitivity to provide insights into the nature of the source through the study of gas ratios and isotopes, they say.
The 2018 ESA ExoMars Rover will search for two types of life signatures, morphological and chemical, with an accurate study of the geological context. Morphological information related to biological processes may be preserved on the surface of rocks or under the surface. The ExoMars drill has been designed to penetrate the surface and obtain samples from well-consolidated (hard) formations, at various depths, down to 2 metres. And 2018 is right around the corner.
The US MAVEN mission to Mars arrived in September, 2014, just in time to duck the Siding Spring meteor. MAVEN is an orbiter that can also look for methane while it studies the Martian atmosphere and serves as a relay for the several rovers still operating on Mars.
However, not long after MAVEN arrived at Mars, NASA scientists at Goddard Space Flight Center and the JPL team lead by John Grotzinger dropped a major bombshell declaring that they had indeed discovered and analyzed a significant methane spike near the rover in Gale Crater. They also began publishing a set or remarkable papers offering scientific proof that the Sample Analysis at Mars (SAM) instrument suite on NASA's Curiosity rover has made the first definitive detection of organic molecules at Mars.
In October of 2013 NASA had reported that perchlorates and chlorinated hydrocarbons were detected by SAM after long months of processing the data from the samples at Rocknest. But the samples were tainted by a leak within the SAM sample manipulation system of the reagent MTBSTFA. The MTBSTFA stored on board was supposed to be secured in five sealed cups until one could be mixed with a robust soil sample to reduce larger organics including amino acids for low temperature processing in SAM. This was the tool to avoid pyrolitic examination.
The scientists used a bank of laboratory analog experiments on earth that suggested that the reaction of Martian chlorine from perchlorate decomposition with terrestrial organic carbon from the MTBSTFA during pyrolysis can explain the presence of three chloromethanes and a chloromethylpropene detected by SAM.
While their paper said there was “No definitive evidence of Martian organic carbon at the Rocknest carbon source for these chlorinated hydrocarbons,” other laboratory work was suggesting a more positive outcome for martian soil dug at Yellowknife. Hence the paper added, “ nor do we exclude the possibility that future SAM analyses will reveal the presence of organic compounds native to the Martian regolith.”
Later, working with the Rocknest tainted samples, then the samples from Yellowknife over the span of 12 months, a huge team of scientists devised a way to work around the contamination in the spaceship laboratory and duplicate the contamination in labs on earth. Once they were certain about the level and nature of the MTBSTFA vapors and their impact on sample analysis, they published a set of definitive conclusions. Yes there are organic molecules native to Martian soil. And, yes there is methane being released on Mars.
"That we detect methane in the atmosphere on Mars is not an argument that we have found evidence of life on Mars, but it is one of the few hypotheses that we can propose that we must consider as we go forward in the future," Dr. John Grotzinger, Curiosity project scientist at the California Institute of Technology in Pasadena, said on Dec. 16 in a news briefing at the American Geophysical Union's convention in San Francisco.
"It's a big day for us - it's a kind of crowning moment of 10 years of hard work - where we report there is methane in the atmosphere and there are also organic molecules in abundance in the sub-surface," Grotzinger said.
It took two years to determine that only some of the organics were not brought to Mars by the Curiosity lander, an unfortunate calamity averted by the rare and unique chemistry of MTBSTFA. Nevertheless early on, in April 2014 project scientist Grotzinger proposed a more lively extension of mission.
“The MSL mission appears to be on the cusp of evolving from a mission, “initially seeking to understand the habitability of ancient Mars (and doing it successfully), to one focused on developing predictive models for the preservation of Martian organic matter. This is not just important for the continued success of MSL, but also for the proposed Mars 2020 mission, which would seek to find promising materials for possible return to Earth. We intend to apply this developing exploration paradigm in searching for organics at Mt. Sharp,” Grotzinger wrote.
However, spanked by the NASA Planetary Acience Mission Review panel for insufficient science at missing their meeting, Grotzinger agreed in June, 2014 to take over the Geological and Planetary Science Division at Caltech.
“Our mission is turning a corner,” Grotzinger said on the way out the door. “We are beginning to map a way forward, a way to explore deliberately for organic matter.”
The fight against sterilization
For 60 years geologists and planetary scientists have argued against spacecraft sterilization for missions to Mars. Bruce Murray, years before he took over Jet Propulsion Laboratory, wrote papers critical of the exobiologists including Dr. Joshua Lederberg and Carl Sagan, accusing them of “transscience.” Murray insisted they misunderstood “the significance of their observations,” because they would not agree with the negative results of the first three JPL Mariner Mars flyby missions. There is much about that in this book.
A pet project of Murray, the cameras on Mariner 4 showed a small blurry patch of Mars that looked as dead as the Moon. Early atmospheric data suggested that running water could not exist on Mars because of its thin atmosphere. Soon after Mariner 4, Murray and Caltech’s biology professor, Dr. Norman Horowitz, called for an end to the bioburden reduction treatment before the Viking mission because, he said, the potential for life on Mars did not justify the cost. In the end, the exobiologists won for the Viking Mission, but no mission after Viking has been so treated.
Considering the costly decontamination of Mars or other extraterrestrial expeditions, it makes no sense to NASA budget builders to do anything but plan. No one on Earth can afford the basics, let alone the equipment necessary to decontaminate the lander on Mars, decontaminate the return container, the return vehicle, the reentry vehicle, and the Earth-based equipment that would handle the returned sample at the levels required by the rules: One-in-a-million chance of microbial contamination.
Yet the Mars 2020 lander, unveiled in July of 2014 has a contingency plan to store the core samples it collects for future delivery to Earth. And the Mars 2020 experiments are planned to reduce the ambiguity inherent in the data reported by Curiosity. Two different experiments using different techniques will analyze the key samples of Martian regolith for organic matter. Scientists on Earth will compare the results, as they have with the SAM samples. The key effort to reduce ambiguity is the decision to eliminate the destruction of samples by intense heat, called pyrolization, as a step in analyzing the samples.
In the GCMS on Viking and Curiosity, samples were vaporized; reduced to their most basic elements by pyrolization and then examined in a spectrometer. The Viking gas chromatograph mass spectrometer (GCMS) required the organic matter contained in about one million Earth microbes in order to detect organics. Since Viking, it has been learned that the heat (500 deg. C) applied to pyrolyze the samples prior to analysis would have destroyed any organic matter present, leaving virtually nothing to examine and report. But the Viking GCMS did report chloromethanes that were considered to be terrestrial contaminants, although they had not been detected at those levels in the blank runs.
Curiosity’s scientists also suggest strongly that perchlorate is abundant in the Martian regolith based on experiments by the Phoenix Thermal and Evolved Gas Analyzer and those of Curiosity. They suggest the it is likely perchlorate was abundant at the Viking lander sites to confuse the Viking GCMS into concluding that it had detected no organics when in fact there could have been parts per million levels of Martian organic carbon at the Viking landing sites based on the abundances of chloromethanes detected after pyrolysis of the Viking soils.
If that is the case, then the last straw has been broken in the opposition to the positive results of Gulliver, the labeled release experiment that found evidence of microbial activity on Mars in 1976.
Telescopes win the numbers game
The annunciation of the cosmic life calculations this past July by NASA is the declaration of victory by statistical fiat. The announcement that life must exist everywhere means that the astronomers have won this round in the 60 year competition that began with the exobiologists, swung to the engineers, veered to the planetary scientists and created a coalition that could accommodate both Bruce Murray and Carl Sagan in similar roles and in similar goals of using remote sensors – souped up telescopes - to go searching for places where life ought to be, then sniffing for geochemical signatures.
When NASA conceded in July that life must be everywhere it set aside the urgency of actually discovering another example of alien life on Mars or elsewhere that would require a sample return for confirmation. And the core sample scenario as early as Mars 2020 is nothing more than a wish at this time. Instead, NASA has stated that it will search for planets like Earth and study them with ever more powerful telescopes. We cannot afford the far more expensive alternative of sending men to Mars to identify a microbe and return it safely to Earth. The other choice beyond Creation is the solution now offered by NASA: The galaxy is filled with life. The universe is filled with life and time. Later we will find out where it began. In the mean time, the children live here on Earth building better telescopes and larger rocket engines, waiting cautiously to meet their ancestors.