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Curiosity ESA Extreme Organisms Life on Mars Meteorites NASA & JPL Red Planet Pen Water On Mars

The Curious Case for Methane on Mars, methane and active organics discovered on Mars (Issue #32)

 

By:  Nicole Willett

methane molecule 2 drsusanrubinOn December 16, 2014 at the American Geophysical Union conference in San Francisco, a panel of scientists working on the Mars Science Laboratory (MSL) Curiosity Rover data announced what we have all been waiting decades to hear.  John Grotzinger stated unequivocally, “…there is methane occasionally present in the atmosphere of Mars and there are organics preserved in (…) rocks on Mars.”

Why is this important?  All life on Earth that we have discovered so far is carbon based, aka organic.  Carbon is found in the DNA of all life forms on Earth.  Carbon can bind with many other elements to form thousands of molecules that are involved in biological processes.  Needless to say, finding organics and methane is a game changer for all of science, from astronomy to zoology.  Organics in general refer to molecules that are often found as components of life.  We know from studying life forms on Earth that methane is a common organic molecule that is a waste product of bacteria and macro organisms.  In fact approximately 90% of Earth’s methane has a biological origin.  However, about 10% of methane on Earth is a result of geological activity.  According to author Jeffrey Bennett from the University of Colorado, Boulder, “The amount of methane in the atmosphere appears to vary regionally across Mars, and also seems to vary with the Martian seasons.  This has led some scientists to favor a biological origin (…)if the source is volcanic (…) the amount of (…)heat necessary for methane release [could] be sufficient to maintain pockets of liquid water underground.”  Pockets of liquid water would be conducive to life.

blog 32 eath marsThe Earth and Mars have many similarities including a 24 hour and 24 hour 37 minute day respectively, a similar axial tilt causing seasons to occur, a rocky surface with many of the same types of rocks and minerals (which may be used as a source of energy), volcanic activity and hydrothermal vents past and/or present, water that is/was fresh, salty, acidic, and/or basic.  Now and perhaps most important of all, organic matter and methane.  In addition to the aforementioned facts, the fleet of rovers and orbiters that have arrived at Mars have proven an environment conducive to microorganisms existed and may currently exist on the Red Planet.   We know this thanks to the many spacecraft that have visited Mars and sent back ample amounts of data.

blog 32 natgeo3The Viking missions were sent to Mars in the mid 1970’s.  They carried a variety of scientific instruments.  Some of them sampled the atmosphere and some examined the regolith.  The results of these experiments have been studied repeatedly since they were performed.  The Labeled Release Experiment, designed by Dr. Gil Levin, made a controversial and still contested discovery of life on Mars.  Viking also discovered methane at 10.5 parts per billion (ppb) in 1976.  It seems both of these discoveries were discounted over the past four decades.

While utilizing the NASA Infrared Telescope in Hawaii, Michael Mumma, of NASA Goddard, observed methane using ground based instrumentation in 2003.  When he followed up the observations in 2006, the methane had vanished.  Some scientists have stated that is indicative of a seasonal plume.  According to NASA’s astrobiology website Mumma and his team observed 20-60 ppb of methane near the poles and up to 250 ppb near the equator.  It is interesting to note that the levels of methane are significantly higher near the equator where the temperature is higher and possibly more conducive to life.

Concentrations_of_methane_on_Mars esaA decade ago the European Space Agency (ESA) announced they had discovered plumes of seasonal methane on Mars.  In March of 2004, ESA announced that the Planetary Fourier Spectrometer on Mars Express detected about 10 ppb of methane in the Martian atmosphere.  A spectrometer is a device that “looks” at a sample of something, in this case atmospheric gases, and takes reading(s) to determine what molecules make up the sample being observed.  A computer generated graph of some type is then read by scientists to analyze the spectral data.

Although ESA and NASA themselves had previously detected methane on Mars, it was important to for NASA to continue the search, using the MSL Curiosity, on the ground in order to again verify the results.  The public may get frustrated with the continuous “discoveries” of methane, but science is always retesting results to essentially try to “disprove” itself in order to make sure the facts are real.  The Curiosity Rover landed on Mars in August of 2012.  It seemed that almost as soon as the Curiosity Rover started exploring her new home on Mars she discovered a dry riverbed where fresh water once flowed in Gale crater.  When she drilled into the rock dubbed “John Klein” scientists realized that the rock contained what biologists call CHNOPS. That acronym stands for Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur. Those are the six elements needed for all life on Earth to exist.  Another discovery were molecules that included carbon which scientists called “simple organics”.  The most recent and most important discovery includes more complex organic molecules than previously discovered, such as methane and chlorobenzene.  We know Mars is enriched with all of the same chemicals to make life that the Earth has.  This latest and greatest discovery puts to rest the long debate about whether Mars has organics.  Some scientists and laymen have been vehemently denying that it is possible.  For the community of “believers” in Martian organics, we feel Methane SAM graph nasa 2vindicated.

The amount of methane reported over the past forty years on the Red Planet ranges from 5-250 ppb from a variety of sources, NASA, ESA, orbiters, rovers, and ground based Earth telescopes.  Many peer reviewed scientific journal articles have been published regarding Martian methane and the possible explanations for its existence.  Some of the potential sources of methane include the presence of life, volcanoes, hydrothermal vents, and several other geological processes.  Methane breaks up and only has a lifespan of several decades to 300 years, which is a short time on a planetary scale. It then breaks down into water and carbon dioxide.  That being said, since methane is present on Mars, it must be getting replenished biologically or geologically currently.

Over the last few decades scientists have discovered amino acids in comets and meteorites, which we know slam into planets, so it is common sense to see that whether Mars originally had organics or not that organics would have landed there sometime in the last 4.5 billion years.  In 2012 it was announced that even Mercury has organics on its surface.  The moon Enceladus, orbiting Saturn, has organics spewing out of the ice covered surface from the salty ocean below.  It seems that everywhere we look we find organics.  We must ask ourselves, how easy is it to form organics and life?  Is life everywhere?

Mars Society Logo (High quality)“[A] striking aspect of the Curiosity discovery is that the concentration of methane detected varies sharply over time. That can only be the case if the source of the methane is locally concentrated, as a globally spread source could not cause such sharp variations. Thus, there may be a patch of ground relatively close to Curiosity which is the source of the emissions, and, therefore, a prime target to drill in an attempt to find subsurface life. Similar biologically suspect spots may well exist elsewhere. We need to locate such spots, and then send human explorers to drill and find out what lies beneath,” states Dr. Robert Zubrin, President of the Mars Society.

~Humans to Mars as a bridge to the stars

[Images: drsusanrubin.com, NASA, NatGeo, ESA, NASA, TMS]

Note: The article snip above is from the Jan 1977 National Geographic magazine.  Below are the next few paragraphs.

blog 32 natgeo4blog 32 NatGeo1blog 32 Natgeo2

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Curiosity Extreme Organisms Humans to Mars Life on Mars Red Planet Pen Water On Mars

Terraforming Mars (Issue #24)

By:  Nicole Willett

The Sun has an approximate lifespan of ten billion years.  Most scientists believe we are about halfway through that life span.  Recently scientists have stated that the Sun will begin its death throes in about 2.8 billion years.  If humans behave in a way conducive to the health of the planet and themselves, we may still be in existence by then.  If that is the case we must be able to take humanity to a new home.  The Red Planet is a perfect first stop in this process.  He will survive longer than Earth.  But Mars will eventually perish as well.  In that case we must use Mars as a “practice” ground for learning how to take humanity to extrasolar planets in order to spread humanity around the galaxy.

blog 24NASA and other science organizations have been discussing a process called terraforming for a very long time.  Terraform means to make like Earth.  Many proposals have been submitted on the best way to make Mars like Earth.  The timelines proposed have varied from 100 years to 100,000 years.  We must find a balance between moving too fast and too slowly.  If we terrraform too fast, we may end up with a runaway greenhouse effect similar to what we see on Venus.  If we move too slow, we run the risk of other complications, such as the natural rhythms of the Red Planet changing during the process which could interfere and complicate any progress we may be making.  Terraforming Mars is of utmost importance in order to learn to live on other worlds.  Humanity must have the ability to be a multi-planet species in order to preserve Homo sapiens for millions or billions of years.

How could we go about terraforming Mars?  The 1,000 year plan seems to be a reasonable timeline.  If you utilize a version of Dr. Robert Zubrin’s, President and Founder of The Mars Society, Mars Direct plan, we would send up a series of habitats ahead of humans.  An automated system to manufacture fuel on the surface of Mars would be included in the initial payload.  This would allow the visitors to Mars to have a fuel supply ready for the return to Earth at a later date.   Humans would then take the six month trip and each crew would stay for 18 months, some may eventually choose to stay on the Red Planet.   Crews of Marsonauts would have an enormous responsibility to lay the groundwork for future Martians.

blog 24 natgeo3The first visitors would set up the habitat modules and start the greenhouse work.  When each successive group arrives at the initial home base, all necessary groundwork will have been laid for them to immediately begin working on the next set of tasks. This may include creature comforts.  In order for the settlers to feel at home on Mars, the habitats would need to be comfortable and roomy.  We would like the crew to feel at home, which will help with psychological concerns.  The greenhouses must also be a top priority.  COis already present in the atmosphere of Mars for plants to utilize for respiration, and they will return the favor by “exhaling” breathable O2 for the settlers.  Humans may feel depressed and isolated, but the aesthetic value of plants could make them feel more at home.  Plants will also serve as a major source of food which is essential to our survival.  They will also provide oxygen for breathing.  The Curiosity Rover has confirmed that the Martian soil is at least 2% water, so we will be able to heat up buckets of soil and extract water for plants and it must also be used for human consumption.  The H2O can also be divided into hydrogen for fuel and oxygen for breathing when necessary.  After we have perfected plants in greenhouses on the Red Planet, we may be able to allow bacteria and lichens, which are able to survive in arctic environments, to grow on the outside of the habitats and greenhouses.   The rovers on Mars have confirmed that the soil is already conducive to certain types of plants.

blog 24 natgeoNow we are ready for the next set of terraforming duties.  What is needed next is a nice thick and warm atmosphere.  Several suggestions have been proposed as to which approach for this is best.  Ideas have been as varied as giant orbiting mirrors to nuclear explosions and everything in between.  A common suggestion has been to release the CO2 frozen in the soil and in the polar ice caps into the atmosphere using factories spewing out what we consider greenhouse gases on Earth.  Whichever tactic is utilized to thicken the atmosphere, once it is warm enough for the polar ice and ground ice to melt and turn some H2O to liquid and some to gas then we are well on our way to add more complex plant life.  The water cycle should begin to look more Earthlike.  Rivers should start to flow, seas will develop, and rain will fall.  Regular weather patterns will develop and Martian meteorologists will surely scramble to predict weather as they do now on Earth.  Next we will add insects and flowering plants.  The soil will become more enriched with the addition of each more complex organism.  This will allow for the addition of even more complex plants and animals in succession periodically, for instance large trees will allow forests to take hold.

blog 24 natgeo2Energy is a must for the spread of civilization.  It is hoped that we have learned from our mistakes on Earth, and we will use all clean energy with little waste on Mars.  Transportation and city planning systems will be developed.  An entire new branch of humanity will start to evolve on the new Mars.  Plants and animals will grow and change over time being separated from their parent species on Earth.  Entire ecosystems will develop on their own trajectory, separate from all life on Earth.  Over the 1,000 year period Mars will be turned from a vast desert with a coral sky into a bountiful planet full of life with a beautiful blue sky.  It may look similar to Earth, but the inhabitants will become truly Martian.

Recently Dr. Zubrin spoke about the importance of humanity rallying from different countries to go together to Mars.  This is an important step in terraforming the planet.  We are all aware that people from all over the world may have important contributions to make to a manned mission to Mars.  Our lack of sociological maturity should not stand in the way of such a humanity altering event.  Borders on maps should not prevent the forward motion of science, technology, and exploration.  It is time to band together as Earthlings to accomplish this goal.  There is nothing beyond our technological ability to stop us from reaching Mars and settling there.  Terraforming is the next necessary step in this plan.

[Images: Wikipedia, NatGeo, NatGeo, NatGeo]

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Extreme Organisms Guest Blogs Humans to Mars Life on Mars Water On Mars

Why Could We Be Descendants of Martians? (Issue #22)

By: Dr. Steven Benner and Nicole Willett

For many years, scientists have considered the model that life originated on Mars and was transported to Earth, rather than originating on Earth.  This model turns on answers to the question: What molecular structures are necessary for biology to “switch on”, moving from an inanimate state to a living state, where reproduction and adaptation (key parts of Darwinian evolution) are able to allow life to manage challenges to its blog 22 dnaexistence. For many, this switch requires the emergence, from a “prebiotic soup”, genetic molecules such as DNA and RNA. And, if this is true, the model then turns on the questions: Could genetic molecules have emerged on Earth? Could they have emerged on Mars? And given what we think about the environments on early Earth and Mars, which were more suited for the kinds of prebiotic chemistry that might give genetic molecules?

Dr. Steven Benner, of the Foundation for Applied Molecular Evolution in Florida, presented findings at the Goldschmidt Conference in Florence, Italy last week that suggest that Mars was more suited. His research increases the chance that life originated on Mars and was transported to Earth via meteorites.  Some people say this is an outlandish claim, while others are becoming more intrigued by the facts that support this model.

To understand this subject, let’s start with some background information about chemistry and biology.  Chemistry is the study of the elements (atoms) on the periodic table and how they connect and interact to make up everything in the universe, including you.  Prebiotic chemistry is the study of how complex molecules that might allow the “switch” to biology might have emerged without life. Models in prebiotic chemistry describe how these non-biological molecules might, under defined conditions, somehow become biological.  The missing link is the “somehow become biological”.  Many studies and journal articles have been published on this subject.  Some have been found to be incorrect and others linger with unanswered questions.

blog 22 single cell fsu eduThe first form of life was, we presume, a single celled organism.  Even so, the cells were complex compared to the prebiotic molecules that preceded them.  The most important elements to early cells are, we presume, also those important to modern biology: carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. These were almost certainly combined on early Earth and Mars, first into small molecules (hydrogen cyanide, for example, HCN, or water HOH, or formaldehyde, HCHO). Processes are known where they can be further assembled (without life) to give components of genetic molecules, including the nucleic acid bases adenine, thymine, uracil, guanine, and cytosine. These bases are the individual letter codes commonly seen in articles and television shows where people check DNA tests.

But here the chemistry becomes more difficult. To further assemble these units into genetic molecules like RNA (believed to be a precursor of DNA), several things must happen. First, the organic molecules present on early Earth and early Mars, must avoid decomposition. As anyone knows who has left the stove on too long in the kitchen, organic molecules given energy tend to devolve into tar. For RNA to have a chance of emerging prebiotically, the devolution of its building blocks must be prevented.

In Florence, Benner presented evidence that minerals (like borax) containing the element boron (in the form of borate) are able to prevent this devolution. Borate captures carbohydrates that are formed in the prebiotic soup before they devolve to a tarry fate.

blog 22 meteor maryland weatherSecond, the atoms in the borate-captured carbohydrates must be rearranged to give ribose, the “R” in RNA. Dr. Benner presented the results of experiments that showed that minerals containing the element molybdenum (in its oxidized form, molybdate) can do this rearrangement.

Third, the ribose must be attached to adenine, uracil, cytosine, and guanine, each by forming bonds that are not easily formed in water. Then, phosphate must be added, also by forming bonds that are not stable in water. To do this, the amount of water available must be controlled; from time to time, the mixture must dry out.

This is all simple enough in the laboratory today. However, Dr. Benner pointed to models from geologists who hold that water was so abundant on early Earth that no dry land was available. Further, these models suggest that borate could not have been presented in useful concentrations. They also suggest that early Earth was insufficiently oxidizing to give molybdenum in its oxidized molybdate form. In short, geologists were suggesting that RNA could not have emerged on early Earth, at least not by way of the prebiotic chemistry that Dr. Benner has proposed.

blog 22 MarsAsteroidImpactHowever, conditions on Mars appear to have been more favorable for Benner’s prebiotic chemistry. First, Mars has always had less water; it was easier to dry out on Mars. This should have allowed borate to be concentrated. Mars may have also had a more oxidizing environment, allowing for molybdate. Finally, phosphate may have been more accessible on early Mars.

We know of this thanks to the orbiters, landers, and rovers that have been studying Mars for nearly 40 years.  We have also collected a large number of meteorites that have come from Mars.  These meteorites contain, among other things, borate minerals and other species that Benner’s prebiotic chemistry requires for the formation of RNA, which is believed to be a predecessor to DNA.

But even if Mars was a more suited planet for life to form, that life must have come to Earth. The idea that life is delivered to one planet from another is called panspermia.  This is certainly possible. About one kilogram of Mars comes to Earth every day, after it is flung from Mars into the Solar System by a meteorite impacting on Mars. The low surface gravity of Mars makes escape from the Red Planet easier than from Earth. Reentry is sufficiently fast that microbes that originated on Mars would survive, arriving on Earth without damage. Here, they would find a planet that was habitable, able to sustain life, even Earth was not suited for life to originate in the first place.

blog 22 icebreaker model nasaTo further this analysis, we must fund and support missions to Mars that include new technology, such as the Icebreaker Mission.  This mission has a six foot drill that will drill beneath the surface of Mars in order to get samples that are far enough below the surface to be shielded from harmful UV radiation.  We must also fund and support missions that will send humans to Mars.  We need humans on Mars in order to respond imaginatively to uncertain conditions on the planet, required to do the appropriate science with the proper laboratory equipment in order to get the answers that have eluded us for decades, possibly centuries.  We need to find life on Mars in order to compare the DNA of the Martians to the DNA of the Earthlings.  Could we all be Martians?

“The emergence of life on Earth might have been an inevitable consequence of the laws of physics, and if that is true, then a living cosmos might be the only way our cosmos can be”   [Professor Brian Cox]

[Images: Benner, FSU, Md Weather, Spaceports, NASA]

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ESA Life on Mars NASA & JPL Red Planet Pen

Will Drilling Find Extant Life on Mars? (Issue #21)

by: Nicole Willett

blog 21 family portraitI recently attended the online NASA/JPL Mars Exploration Program Analysis Group (MEPAG) meeting that was held on July 23, 2013. The meeting’s purpose was to discuss the Mars 2020 rover and many other Mars exploration issues. Many people wonder why NASA keeps sending rovers to Mars without stating that they will unequivocally search for extant life. The term extant means, still in existence.   We know that MSL Curiosity has the equipment to detect life and that Mars 2020 will have many of the same instruments. However, Jack Mustard, Brown University professor, who presented at the MEPAG meeting, stated, “To date, the evidence that we have from observations of Mars and Martian samples is that we don’t have the clear indication that life is at such an abundance on the planet that we could go there with a simple experiment like Viking [had] and detect that [life is] there.” Mustard went on to explain that it makes more sense financially and scientifically to search for past life instead of current life. He believes that we must continue studying the past geology of the planet in order to better understand whether past life existed on Mars.

As we anxiously await the analysis from Curiosity’s second drill sample, which was taken on May 20, 2013, we can discuss the search for present life on Mars. As indicated above the Mars 2020 rover will not search for extant life. Some people do not understand why we must wait seven years to launch a rover similar to MSL with a sample return cache that will sit on the planet for an unknown period of time with no plan as to how it will be returned to Earth. However, there are other missions planned for Mars which may search for and possibly find current life on Mars. Two such missions are ExoMars and the Icebreaker Life Mars mission.

blog 21 exomarsExoMars is collaboration between the European Space Agency and the Russian Federal Space agency. It is a mission that includes an orbiter and lander planned for 2016 and a rover with a drill that can reach two meters beneath the toxic surface, planned for 2018. The 2018 mission objective is to search for past or present life on Mars. During the MEPAG meeting, the question was asked, “What if ExoMars finds life, and how will that affect Mars 2020?” The answer was given by Jim Green, Director of NASA Planetary Science, who stated, “It would be a great problem to have.”  This also started a discussion about whether this would be a “Sputnik moment” and possibly encourage a new race for humans to Mars.

The Icebreaker Life mission could also be funded for a 2018 launch under the Discovery/New Frontier program, a separate funding scheme like the 2016 Insight mission. In a paper published in the journal Astrobiology on April 5, 2013, Dr. Chris McKay, Dr. Carol Stoker, and other leading scientists stated, “The search for evidence of life on Mars is the primary motivation for the exploration of that planet. The results from previous missions and the Phoenix mission in particular, indicate that the ice-cemented ground in the north polar plains is likely to be the most recently habitable place that is currently known on Mars.” The goals of the Icebreaker Life mission include:

“(1) Search for specific biomolecules that would be conclusive evidence of life.

(2) Perform a general search for organic molecules in the ground ice.

(3) Determine the processes of ground ice formation and the role of liquid water.

(4) Understand the mechanical properties of the Martian polar ice-cemented soil.

(5) Assess the recent habitability of the environment with respect to required elements to support life, energy sources, and possible toxic elements.

(6) Compare the elemental composition of the northern plains with midlatitude sites.”  [Source: http://online.liebertpub.com/doi/abs/10.1089/ast.2012.0878 – Journal Astrobiology 4/5/2013]

This mission is very similar to the Phoenix lander but will have more advanced scientific equipment, including a drill that will reach a meter below the surface, an instrument called the Signs of Life Detector (SOLID), an Alpha Particle X-ray Spectrometer, a Wet Chemistry Lab, and many other instruments. This combination of instruments may potentially alter how we view life in the universe. The SOLID instrument has the ability to detect compounds with a biological origin such as whole cells and complex organic molecules.  It has an advanced digital camera and what is known as a “lab on a chip” that can perform various chemistry tests using equipment the size of microchips. The technological advances being made are greatly improving the field of robotic exploration and experimentation in ways never thought possible in the past.

DCIM100GOPROThe Icebreaker Life mission will search for biomarkers in the same region near the north pole of Mars where the Phoenix Lander executed its mission in 2008. A biomarker is any molecule that indicates the presence of life, such as an enzyme.   These biological molecules carry organic biochemical information. The Icebreaker drill is capable of drilling one meter into the subsurface of the Red Planet in order to search for biomarkers. The ice shavings retrieved from the drill would be analyzed for molecules that are too complex to be present from a non-biological source. It is important to drill below the surface in order to retrieve samples that have not been exposed to the radiation and perchlorates (salts) that exist on the surface of Mars. The radiation and perchlorates could potentially destroy any biomarkers or biological material present, hence the importance of a subsurface mission.

Many opinions exist regarding the search for life on Mars, past or present. The sheer number of planned missions is a clear indicator of the widespread scientific interest. When asked about the search for life on the Red Planet, McKay stated, “Why search for a second genesis of life? The implication is that life is common in the universe.”

[Images: NASA, ExoMars, Astriobio.net]

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Curiosity Life on Mars Red Planet Pen

What is Life and Will Curiosity Find it on Mars? (Issue #14)

by: Nicole Willett

The definition of what life is has eluded scientists for many generations…

This is partially due to the many extreme organisms that have been found that push the traditional boundaries outward in every direction.  What is a virus? It can reproduce, but it is considered not to be life because it must have a host to reproduce.  Does size matter?  Can something be too small to be alive?  There are bacteria that are smaller than viruses.  Can something be too big to be alive?  Recently, I have heard scientists debating whether the entire universe is a living organism.  In order to come up with a definition we must describe what elements are needed for life as we know it to exist.  We must also decide whether or not water is necessary and in what state.  Can organisms live in soil with a high or low pH content?  Are there energy gradients available for an organism to utilize the chemicals available for metabolism?  What temperatures can life survive at?

blog 14 jonlieffmd comAll of these questions must be addressed before scientists come up with a true definition for life.  A simple definition of life from dictionary.com states, “the condition that distinguishes organisms from inorganic objects and dead organisms, being manifested by growth through metabolism, reproduction, and the power of adaptation toenvironment through changes originating internally.”  This definition may work for laymen but when it comes to the plethora of extreme organisms we are finding now and with the search for organisms on Mars, we need a much more specific definition.  As with all things in science, we have had a hard time getting everyone to agree on a true definition. 

Some things to consider are the six required elements necessary for all life on Earth thus far.  Biologists like to call it CHNOPS.   

Blog 14 nasa jpl

That acronym stands for is Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur.  Interestingly, the Curiosity Rover’s SAM and CheMin instruments found CHNOPS in their latest sample of the rock called “John Klein” that was drilled recently.  These results can all be found on NASA and JPL websites.  Another interesting find is methane in the forms of chloromethane and dichloromethane.  These are widely reported as “simple organics” in the press.   These molecules were also found at the “Rocknest” site in an earlier soil sample taken by Curiosity.  The discovery of organic molecules is the pièce de résistance that we have all been awaiting.   Organics in general refer to something that was at one time alive or is alive now.  We know from studying life forms on Earth that methane is a common organic molecule that is a waste product of bacteria and macro organisms.   However, about 10% of methane on Earth is a result of geological activity.  The rovers and orbiters have not detected any macro organisms, but scientists are diligently looking for evidence of an environment conducive to microorganisms. 

blog 14 nasa jpl 4betterAgain the scientists caution that these results may be contaminants from Earth.  But, this seems to be a pattern.   Mars scientists are repeatedly confirming and reconfirming the presence of water on Mars.  Also, they are stating and restating the potential habitability of Mars.  Dr. John Grotzinger, project scientist for the Curiosity mission, went so far as to state, “”We have found a habitable environment.  The water that was here was so benign and supportive of life that if a human had been on the planet back then, they could drink it.”  Wow, that is quite a statement.  Not only are NASA scientists stating that Mars was habitable they are stating that humans could have consumed the water that sat and flowed on the surface of the Red Planet.  Think about the potential ramifications of that information. 

As the scientists, go over and over the information from Mars, they continue to make amazing discoveries.  Another significant find is the electrochemical gradient of the different molecules found inside of the John Klein rock.  An electrochemical gradient is another important piece of the “life on Mars” puzzle because life forms use these gradients to move ions across membranes in order to perform many metabolic and other biological functions.   Some of the molecules found in the rocks have different electric charges; some are more oxidized than others.  This was cleverly illustrated at last week’s press conference.  Dr. Grotzinger held up a battery to demonstrate the way rock eating microbes utilize the energy gradients formed by molecules, such as sulfates and sulfides, to their advantage in their metabolic processes.  This finding has extraordinary implications if everything that has been reported remains true. 

blog 14 psrd hawaii edu

So, what is life and will Curiosity find it on Mars?  Well, we know that there is no single definition that everyone agrees on.  Keep in mind that the requirements for life as we know it are: water, a source of energy, and evidence of organics.  The types of methane found are known as simple organics. However, we also know that there are definite signatures for life as we know it.  NASA is finding more and more evidence with every scoop of soil analyzed by Curiosity’s onboard lab.  If the day comes when there is a confirmation of life on Mars, it will change humanity forever.  I am looking forward to that day.
[Images: NASA JPL, jonlieffmd.com, psrd.hawaii.edu]