When Curiosity had been few months in Mars, Curiosity principal investigator John Grotzinger announced that they will keep a press meeting about findings. Pre-information was that they will be 'Earth shaking and for the History books'( Universe Today 20.11.2012: Has Curiosity Made an ‘Earth-Shaking’ Discovery? ). Week went by and the press meeting came. The scientists were quite quiet. Normal things of Curiosity ongoing mission were told. Looks like at last minute NASA decided not to tell the Earth Shaking news. But in meeting it was mentioned that the conditions in Mars are such that if there is signs of past life, they would be well preserved. Now things have been processed further. We have theory by Steven Benner to explain findings. We know that life, in form of microbes carried by meteorites, survive the trip from Mars to Earth . We have explanation why life on Mars resembles life on Earth.
NASA has been strangely cautious in telling about findings related to possible life on Mars. Some clarification about NASAs policy for publishing news is given by this interview of John Grotzinger, November 2012: Big News From Mars? Rover Scientists Mum For Now . So NASA scientists cannot tell about their findings until they have done a scientific publication, for instance in the Science magazine or in conference like Lunar and Planetary Science Conference (LPSC). They are not allowed to speak even to family members at home. Rather strange rules by NASA in science world. There should be open and free discussion in science. Just looking at pictures in this web-page it is easy to say that Mars is a planet of past and current life.And that Mars has gone through a long evolution process producing higher forms of life, not just microbes.
NASA gives almost all pictures of Mars-rovers to archives for anybody to see. Curiosity has produced 481000 pictures, Opportunity 226000 and Spirit 128000. Only the amount of pictures, 835000, is huge. And then there is all the science data from instruments. It takes time to analyze all the data and produce science publications.
On 9th of December 2013 Curiosity science teams published 6 remarkable articles in Science magazine. The main message of these articles is that Mars has been habitable. It had good conditions for Life. In these articles it is also told that the chemical analysis instruments onboard Curiosity found organic compounds on the samples. And also life is given as one possible explanation alternative for white veins and nodules discovered by Curiosity. See Science magazine Curiosity web-page: http://www.sciencemag.org/site/extra/curiosity/ and there article New Results Send Mars Rover on a Quest for Ancient Life .
On December 30 2013 the Curiosity principal investigator John Grotzinger wrote a very interesting blog: Habitability, Taphonomy, and Curiosity’s Hunt for Organic Carbon . For first time, in relation to Mars, he discusses fossils and Charles Darwin 's evolution theory , which Darwin published in 1859 in his book On the Origin of Species. Taphonomy is the term paleontologists use to describe how organisms become fossilized. John tells also in his blog about the history of science, how it was difficult to prove the evolution theory correct on planet Earth. It took 100 years in scientific community to establish evolution theory.
John Grotzinger explains in 24th of January 2014 Science magazine web-article Habitability, Taphonomy, and the Search for Organic Carbon on Mars that they have certain principles for searching life on Mars. Curiosity has a lot of science and chemical analysis instruments. The analysis results must show that Mars was habitable and had good conditions for life. If analysis would show that conditions for life in Mars were impossible, then there would be a big contradiction to see fossils in the images in Curiosity and Opportunity. The remarkable thing is that in 9.12.2013 publications in Science magazine it is shown that Mars was habitable and had good conditions for life.
Interesting meeting concerning Mars was on 17-21 of March 2014 in Woodlands, Texas: 45th Lunar and Planetary Science Conference . In this meeting over 300 articles concerning Mars was published. Detailed analysis result of Curiosity and Opportunity chemistry data was presented. Several studies and laboratory test results of how micro-organisms survive in conditions of planet Mars was presented. In this link you can access all the abstracts. Check also the test results from International Space Station, which showed that microbes survived during 1.5 years test period in extreme conditions of empty space: Space Station Research Shows That Hardy Little Space Travelers Could Colonize Mars .
On 28th of September 2015 NASA held a press conference to announce the confirmation of liquid water on today’s Mars. In the introductory speech of the conference astronaut John Grunsfeld, Science Mission Directorate, says: We try to answer fundamental questions..are we alone....we send astrobiologists and planetary scientists to Mars....to explore the question is there current life on Mars.
What is remarkable is that the chemistry and low atmospheric pressure of Mars keeps the water liquid in temperature range -70 degrees Celsius to +10 degrees Celsius. That means that at equator of Mars the water mixed in the soil is in liquid state almost all the time. And there is moisture in the air. This gives good conditions for life on present day Mars. So the old official view by NASA that Mars is a dry and lifeless planet is now swept away. The implications for life on Mars and planetary protection were taken up in the conference frequently. The liquid water was identified by investigating Recurring Slope Lineae (RSL), which are traces of water flow. There is RSL activity also in Gale Crater close to Curiosity, according to article: Icarus 2015, Colin M. Dundas, Alfred S. McEwen, Slope activity in Gale crater, Mars.
See also articles: Universe Today, by Ken Kremer on September 28, 2015: NASA Discovers Salty Liquid Water Flows Intermittently on Mars Today, Bolstering Chance for Life and NASA, 28.9.2015, NASA Confirms Evidence That Liquid Water Flows on Today’s Mars . And see 7th of October 2015 blog post Patrick Rowan's Skywatch: Mars has liquid water, could it have life? .
The NASA Viking space crafts landed on Mars planet in 1976. These 2 landers carried the first ever instruments to analyze possible existence of life on Mars: Labeled Release (LR) experiment. The LR instrument was designed by Gilbert V. Levin and Patricia Ann Straat . The principle in LR experiment is that sample containing possible microorganisms, is given radioactive food. If sample contains microorganisms then radioactive gas, which can be observed, is released from the sample. Gilbert and co-investigator Patricia Ann Straat found out from LR data that both Viking landers about 7000 kilometers from each other gave positive result for existence of microbial life in Mars. These results and the test setup have been heavily debated after that. Unfortunately, for some reason, for very long time NASA has tried to disprove the results from LR experiment and state that "Mars is a dead planet". Now seeing the new experimental and visual evidence for life on Mars by Curiosity and Opportunity, it can be concluded that Gilbert and Patricia, with Viking LR data, were the first ones to discover microbial life on another planet, Mars. Achievement worth of Nobel prize.
Barry DiGregorio, Gilbert Levin and Patricia Ann Straat wrote 1997 the astrobiology classic MARS The Living Planet and later 2011 update The Microbes of Mars . Year 2019 Patricia wrote an excellent book To Mars with Love about LR experiment.
Read also: Gilbert V. Levin: Chapter Nine - Life After Viking: The Evidence Mounts , Barry E. DiGregorio: The Viking Labeled Release experiment controversey: Why does it exist and when will it end? and Gilbert V. Levin 2016, Extant Life on Mars: Resolving the Issues .
The Vikings contained 4 main experiments. The LR, GEx and PR which were life detection experiments and Gas chromatograph GCMS. These were tested extensively with samples from Antarctica, Death Valley desert and Moon before sending them to Mars. The LR was the most sensitive. It could detect 10 living bacteria in a sample. The GCMS needed one million microbes in a sample. Only LR could detect life from Antarctica deep ice samples. The GCMS was having problems already at Earth test and it failed frequently in Mars. It was not even sure if samples went inside GCMS. Despite of that NASA has stated that "Vikings did not detect life", since GCMS did not detect organic matter. Curiosity has detected large amounts of organic matter[32, 108]. Dr. Jennifer Eigenbrode from the Curiosity organics team has stated that “organics are all over Mars, all over the surface, and probably through the rock record" . Read Jennifer L. Eigenbrode, et all , Science June 2018: Organic matter preserved in 3-billion-year-old mudstones at Gale crater, Mars .
Also the Phoenix lander 2009 mission results have indicated that even Viking GCMS results show organics on Mars [109]. See also article in Universe Today by Paul Patton, January 6, 2015: Defining Life II: Metabolism and Evolution as clues to Extraterrestrial Life . I quote the article, stating about Viking experiments:...All three experiments produced what seemed like positive results. However, most scientists rejected this interpretation because the details of many of the results could be explained by supposing that there were chemical oxidizing agents in the soil instead of life, and because Viking failed to detect organic materials in Martian soil. This interpretation, especially for the labeled release experiment, remains controversial to this day and may need to be revisited based on recent findings.
In Mars LR made totally 9 tests with all interesting and clear positive results. The LR experiment contained also a method to verify that results are not caused by chemistry of Mars. A control sample was heated to 160 degrees to kill any living microorganisms. After heating to 160 degrees the sample gave a negative result indicating that microbes had died. The really interesting results came when samples was heated only to 46 and 51 degrees. The 51 degree heating lead to positive result of 10 percent compared to sample without heating. The 46 degree heating gave positive result of 30 percent. This would indicate that the temperature where Martian microbes start to die is around 50 degrees Celsius. Similar results in Earth are got with E.Coli bacteria. One overlooked GEx result was that in the experiment the sample did take in carbon dioxide and oxygen was released. Currently Mars has 0.13 percent oxygen content. Mars leaks this to space so a source generating the oxygen in Mars is needed. All the details about these experiments can be read in books MARS The Living Planet by DiGregorio and To Mars with Love by Ann Straat. Carl Sagan was going to write a review of the DiGregorios book, but he died before he had change to do it.
Curiosity rover has observed that the oxygen levels behave the same way as methane levels at Gale crater. They rise to higher level during spring and summer. The rise in oxygen levels is 30 percent. This could be a sign of photosynthetic life. Check for example the blue green material covering stones in these Curiosity Sol 1594 and 1596 images in my Mars photo library. And see the article Universe Today November 2019, Evan Gough Molecular Oxygen on Mars is Behaving Unusually Through the Seasons. A Sign of Life? . Original publication by Curiosity science team: Melissa Trainer(NASA Goddard Space Flight Center) et.al, Journal of Geophysical Research: Planets, 2019: Seasonal variations in atmospheric composition as measured in Gale Crater, Mars . Quote from the summary: Geophysical and geochemical results have painted a picture of a formerly habitable planet billions of years in Mars’ past, and measurements of current processes provide indications that Mars may still potentially harbor habitable environments.
The statements of individual prominent scientists about LR experiment result can be checked from article Gilbert V. Levin, Astrobiology 2015: The Curiousness of Curiosity . See also Gilberts analysis of preliminary data from Curiosity: 8 July 2013, SPIE Newsroom: Evidence for microbial life on Mars? </a>. And Universe Today July 22nd 2015 article Mars , where Matt Williams refers to Gilbert's analysis as "The results of the biological experiments on board the Viking landers were inconclusive, but a reanalysis of the Viking data published in 2012 suggested signs of microbial life on Mars.". At the end of same article Matt comments on the images by current Mars rovers and orbiters: "..They have also shown that organic life can and most likely did live on Mars at one time."
See also YouTube videos by Gilbert V.Levin and Barry DiGregorio:
28.8.2015 Dr. Gil Levin - 18th Annual International Mars Society Convention (30 minutes) .
3.8.2014 But Wait! We've already Found Life on Mars! (24 minutes)
21.6.2010 Life on Mars Interview with Barry DiGregorio and Dr. Gilbert Levin (9 minutes)
3.9.2010 Gilbert V. Levin commentary on the book MARS: THE LIVING PLANET (8 minutes)
And read an excellent articles based on Gilbert V.Levin's interview by Patrick Rowan(USA), 5th of July 2016: Patrick Rowan's Skywatch: 40 years after Viking landing questions remain about life on Mars and 2nd of August 2016: Patrick Rowan's Skywatch: Is NASA running away from life on Mars? .
On October 1st 2016 Gilbert V. Levin and Patricia Ann Straat published article in Astrobiology: The Case for Extant Life on Mars and Its Possible Detection by the Viking Labeled Release Experiment . Dr.Levin and Dr.Ann Straat, get strong support from Chris McKay, PhD, Senior Editor of Astrobiology and an astrobiologist with NASA Ames Research Center in article: Mary Ann Liebert, Oct 18 2016: Microbial life on Mars: The possibility must be considered conclude researchers in Astrobiology . Gilbert and Patricia conclude in their article a recommendation for future Mars research: We strongly recommend that life-seeking experiments be considered for future missions. These should include the continued search for organic molecules of biological importance (e.g., amino acids, simple carbohydrates, lipids, DNA, protein); the conduct of further metabolic experiments, including a search for chiral preference in metabolism; the close examination of any tantalizing surface features; and perhaps even microscopic examination of martian soil with and without the addition of water or water vapor, reminiscent of the experiments of Antony van Leeuwenhock, who discovered the phenomenon of cryptobiosis approximately 300 years ago (Clegg, 2001).
I like the especially including "the close examination of any tantalizing surface features", which is the main content of my visual study and also the content of studies by Dr. Lyall Winston Small and his friends in MRB. Read also a good article by Levin in Scientific American blog 10th of October 2019: I’m Convinced We Found Evidence of Life on Mars in the 1970s and an interesting article on ICAMSR web site: Will the MSR be infected by the COVID-19?
Curiosity Extended mission started in October 2015 and lasts to 2019. UK Space Agency supported (and was ready to fund) a new life detection program proposed by Dr. DiGregorio and Dr.Levin “A search for extant endolithic and hypolithic microbial communities” to be included in extended mission: July 23 2015 University of Buckingham Astrobiologists Endorsed by UK Space Agency to Look for Life on Mars.
The program would use Curiosity's instruments and cameras to detect and study currently living micro-organisms in Mars. Totally there was 89 proposals submitted and 6 of them selected. This proposal was not selected . However Curiosity team has used this proposal on May 2016. Read: Barry E. DiGregorio: 1st of June 2016: New NASA close-up images of freshly broken open rocks by the Curiosity rover wheels could
incidentally verify that the 1976 Viking Mission found microbial life
Year 2002 Dr.Carol Stoker (NASA Ames Research Center) found in Mars Pathfinder mission 1997 data that two areas close to Pathfinder had the spectral signature of chlorophyll . Read: David Whitehouse, BBC News 2002: Life on Mars hopes rised . Chlorophyll is a biomolecule, critical in photosynthesis, which allows plants to absorb energy from light. Chlorophyll is closely related green pigments found in cyanobacteria and the chloroplasts of algae and plants.
Unfortunately these results were not published for a reason, which I handle later in chapter Colors in Mars. Same unfortunate happened to Dr. Daniel Glavin about finding molecules like those in all microbiological membranes (fatty acids), in Curiosity results 2015. Read: Paul Rincon , BBC News 2015: Possible fatty acid detected on Mars.
Both chlorophyll and fatty acids are strong bioindicators. And finding them in Mars is consistent with positive results of Viking LR experiment.
In this article I have collected Curiosity and Opportunity images, which in my opinion clearly show visual evidence for past and present life on Mars. In the images we see objects which change shape over time, grow, are not covered by dust, and look like life. And if we think of Steven Benners theory of life born on Mars these images just confirm the theory by Benner or the Panspermia theory.
In my view the animal fossils (Curiosity Sol-109,Sol-186) and the structural Newberries (Opportunity Sol 3064,Sol 3247) is easy to interpret as past life. The Newberries have internal and external fine structure which is repeated in 2 places far away from each other. It is interesting to see from animal fossils that in Mars evolution has produced 2 eyes for animals as in Earth. Having stereo vision helps to survive in three dimensional world. Was life on Mars only in oceans ? Did it move to land ? Fossil in Sol 109 looks like sea animal. Sol 186 fossil may have certain land like feature.
White objects which change their shape (Sol-173) and the Blueberries may be something like fungi. The Sol-304 object may be stone and minerals eating microbes classified as chemolithoautotrophs. In many places in Mars ground there is white veins with nodules(Sol-192, Sol-270). And from drilling picture of Sol-270 the veins seem to go deep inside ground. For the first time NASA gives as possible explanation for these microbes in article published in Science magazine 9.12.2013: 'A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars'.
Fresh results from Curiosity and from laboratory experiments may indicate Methanogen type microbes in martian soil. Whatever species there exists now in Mars, they have got long time to adapt to current conditions of Mars. Microbial life just below the surface and on the surface transforms the landscape of Mars during millions of years. And it is also a force causing erosion. The landscape of Mars is surprisingly fresh looking. And there is very little dust covering the surface, especially when looking the images, which are correctly white balanced. The traces of current microbial life is in practice visible in almost every image taken by Mars rovers.
NASA has stated that Curiosity is not equipped with life detection instruments. And that images prove nothing in Mars (..but on other planets images are very important: Pluto,..). Now when it seems that there is visible life on the surface of Mars i think that both Curiosity and Opportunity are well equipped to detect life. They have excellent cameras. And then all the instruments in addition. If You want to find life, then look for life!, said Dr.Levin in 18th Annual International Mars Society Convention, August 2015.
About natural resources at Mars: If Mars has long history of life, does it have fossil fuels underground? Oil ? Natural gas (=methane)? There is already 2-6 percent of water mixed in the ground so manned missions do not have to bring water from Earth. Interesting article 11.12.2013 in Universe Today about liquid water on Mars equator is this: Is There Martian Salty Water At The Red Planet’s Equator? These Lines May Be The Smoking Gun .
In Sol 17 image by Opportunity we see that the Blueberries color the landscape with dark blue tone. In chapter Blueberries we saw that one option for Blueberries is Martian fungi. From the orbit of Mars we see large dark areas, like Sinus Meridiani. And Opportunity is located in a dark area. Could it be that Blueberries, possibly a living thing, is the reason for large dark areas of Mars? If so the dark areas would indicate directly where the largest liquid water resources are on Mars. There are seasonal changes in the dark areas of Mars. The dark areas are largest when there is spring and summer and the melted polar ice cap has released lots of moisture to the air. Next time, when you take your telescope and point it to Mars, and You see those dark areas on Mars, you may wonder: "Do I see now Blueberry fields, extraterrestrial life, with my own eyes?"
Excellent, freely readable, observations about life on Mars is by Dr. Lyall Winston Small, September 2015 book: On Debris Flows and Mineral Veins - Where surface life resides on Mars and 2012 book In search of life on Mars . And 2015 book The Living Rocks of Mars
Is it wise to make missions to bring samples of Mars to Earth? Or at first make manned missions with return tickets ? Can Martian microbes harm life on Earth if they are released from laboratory by accident ? Martian Microbes, Viruses and Bacteria can be pathogens, for which we humans and other life forms on Earth have no resistance. These questions lead us to subject of planetary protection , which was promoted already in 1973 by well-known scientist Carl Sagan. When Columbus discovered America, largest part (90%) of Indian population were killed by diseases carried by Europeans. If we go to Mars, can our microbes cause harm to current Mars life ? The Russian (Soviet Union back then) Mars2 crashed and Mars3 landed to Martian surface in 1971. At that time Russia did not care about international COSPAR spacecraft sterilization agreements [63]. Read more about these issues at International Committee Against Mars Sample Return , led by astrobiologist Barry E.DiGregorio .
It is possible that the current Martian life forms could radically change the biology on Earth. They could even cause mass extinctions for species on Earth, including us humans. Now we should postpone the planned manned missions to Mars. Instead we should first carefully investigate the biological properties of Martian life forms. We could establish a test laboratory in the orbit of Mars or in the Moon. In laboratory we could test what happens when life-forms of Mars and Earth get into contact. Because of new findings from Mars, in March 2014 it has been proposed that the rules concerning Special Regions on Mars should be updated: D.W.Beaty, J.D.Rummel 2014: Introduction to an updated analysis of planetary protection “Special regions” on Mars.
Despite of all the tremendous risks for Life on Earth, NASA is planning for a Mars sample return with its Mars 2020 mission which will collect the samples for later returning them to Earth. NASA must be fully aware of the risks. The official view of NASA has been for a long time "There is no proof for life on Mars,so there are no risks".
You could argue that risk is small because microbial exchange with meteors has been going on all the time between Earth and Mars. But when was the last major exchange? When dinosaurs died on Earth? We should be cautious. Think about how microbes like Ebola can change just in few decades in Earth. And then think about risk of taking one million microbes with maybe 1000 new types of viruses and bacteria with unknown properties from Mars to Earth.
The risk for failure in returning them safely to laboratory in Earth may be as high as 30 percent. Instead we may accidentally spread Martian microbes in Earth’s atmosphere, sea or soil and then they start to multiply. Our technology for making safe entry from space to surface of Earth is not mature enough yet.The NASA Genesis sample return mission crashed on Utah 2004 as the parachute did not open, spreading the samples on the desert.
When considering possible risk of Martian microbes to the Earth, it is often stated that Martian microbes would not survive the higher temperature of the Earth. That statement may be completely wrong. The average temperature of Mars is low. But during the day at equator of Mars, the soil temperature can be several hours + 36 degrees Celsius.
So the Martian microbes survive large daily temperature variations of -80 C to +36 C. So they would survive well in most environments on the Earth. And the conditions at Earth could be actually excellent for Martian microbes to start aggressive expansion on Earth biosphere. The fast adaptivity of bacteria to changing environments can be read from: Science Alert Oct 2017, Fiona MacDonald: One of The Biggest Evolution Experiments Ever Has Followed 68,000 Generations of Bacteria .
Between Permian and Triassic period 250 million years ago life on Earth experienced severe mass extinction. Close to 70 percent of terrestrial animal and plant life and 96 percent of sea life died on Earth. It took 10 million years for Earth life to recover with new species emerging. Recent studies have suggested that new type of methanogen bacteria and sulfur interacting bacteria changing the biosphere of the Earth may have played main role in that catastrophic event ( See wikipedia: Permian–Triassic extinction event ). Can we allow NASA to take the risk of bringing Martian microbes with unknown properties directly to Earth?
NASA , Mars One company and SpaceX company are aiming to send first humans to Mars in 2020-2030 decades. The first astronauts in Mars can not avoid the contact with Martian viruses and bacteria. This may shorten their expected lifetime in Mars dramatically. The biological waste produced by humans is spread into Martian soil. Our Earth microbes will start to spread on Mars, changing the current ecosystem of Mars. It can be questioned how ethical this is? Do we have the right to replace or mix the current life on Mars, with life from Earth?
NASA management and SpaceX can keep their current plans of conquering Mars without ethical problems only by keep on claiming that there is no life on Mars. The two way traffic planned by SpaxeX owner billionare Elon Musk will certainly mix the life forms between Earth and Mars. How it is possible that Musk is allowed to break all the COSPAR Planetary Protection rules? Wake up Elon Musk!
According to international law, UN Space Treaty: United Nations Treaties and Principles on Outer Space(2002 Update) and the COSPAR Planetary Protection Policy (2011 Update) NASA and SpaceX are not allowed decide themselves about Mars sample return or sending people to another planet having its own life. These issues must be handled in United Nations. Of course it is a problem that NASA and SpaceX have already spent billions of dollars for planned Mars missions, which now should be modified. Also the political leadership of USA has accepted the NASA manned Mars missions [111] . Currently NASA management acts against UN Space Treaty, Part one, Section E, Article 5, Clause 3:
In carrying out activities under this Agreement, States Parties shall promptly inform the Secretary-General, as well as the public and the international scientific community, of any phenomena they discover in outer space, including the Moon, which could endanger human life or health, as well as of any indication of organic life.
Interesting and comprehensive article about planetary protection is the one linked below, year 2016. Dr. John D. Rummel was NASA’s Planetary Protection Officer until 2006. He has chaired COSPAR’s Panel on Planetary Protection since 1999. Dr. Catharine A. Conley has been NASA’s Planetary Protection Officer during 2006-2017. Dr. Margaret S. Race works for SETI institute, in field of planetary protection, especially Earth and Mars. Mission to Mars: The Integration of Planetary Protection Requirements and Medical Support, 2016 by John D. Rummel , Ph.D, Institute for Coastal Science and Policy, East Carolina University, Margaret S. Race , Ph.D, SETI Institute, Catharine A. Conley , Ph.D, NASA Science Mission Directorate, David R. Liskowsky, Ph.D, NASA Office of the Chief Health and Medical Officer-
Does this article by Rummel, Race, Conley and Liskowsky show a change towards a more strict handling of planetary protection issues in coming Mars missions? I hope so.
On January 2018 Lisa M. Pratt was appointed as new planetary protection officer of NASA. The Planetary Protection issues in European Space Agency(ESA) are taken care of by Planetary Protection officer Gerhard Kminek . See article: Scientific American, November 30, 2016: NASA Outlines Planetary Protection Priorities . And see 2015 workshop report by M.Race, J.Johnson, J.Spry, B.Siegel and C.Conley: Planetary Protection Knowledge Gaps for Human Extraterrestrial Missions. Also J.D.Rummel participated the workshop. The planetary protection officers Conley and Kminek, hopefully do good work in this matter.
See also comprehensive article by Robert Walker, March 2016: Can We Risk Microbes From Human Crashes - On Mars? If Not, What Happens To Dreams To Colonize The Planet? . And read article by Dr. Kelly Smith, May 2016: Do no harm to life on Mars? Ethical limits of Prime Directive . Dr. Kelly Smith is Professor of Philosophy & Biological Sciences in Clemson University. He organizes conference series Social and Conceptual Issues in Astrobiology .
Funded by European Comission there is EURO-CARES project , which is planning to build facilities for astromaterials potentially containing extraterrestrial life. Samples from Mars would be stored there. It is worrying to see this kind of preparations. See related article , Neel V. Patel November 17, 2016 Inverse: Alien Lifeforms Will Have an Apartment in Europe .
Changing planet Mars back to habitable planet for mankind (Terraforming) has been studied for a long time. A good article about this is by Christopher P. McKay, 2007: Planetary Ecosynthesis on Mars: Restoration Ecology and Environmental Ethics . According to the report Mars can warmed up with super-greenhouse gases in 100 years. Producing breathable oxygen atmosphere with microbes and plants would take from few thousands of years to 100000 years. McKay has also great thoughts about ethics and what to do in case we find life on Mars. McKay is working in Curiosity Science team.
It is possible that even the planet Mars is not the origin of life in our Solar System. It is possible that our solar system received the original seed of Life carried by meteorites, from some other nearby stars having life on its planets. The original term for this theory is panspermia. This kind of idea was presented for first time by creek philosopher Anaksagoras 500 BC. Modern versions of panspermia have been developed by Svante Arrhenius , Sir Fred Hoyle and Chandra Wickramasinghe. Chandra is the director of Buckingham Centre for Astrobiology (BCAB) .
Interesting articles about panspermia are W.M.Napier and N.C.Wickramasinghe 2010: Mechanisms for Panspermia and Rhawn Joseph and Rudolf Schild 2010: Origins, Evolution, and Distribution of Life in the Cosmos: Panspermia, Genetics, Microbes, and Viral Visitors From the Stars .
One more interesting article is Rhawn Joseph 2014: Life on Mars? Evidence for Moisture, Algae, Fungi, and Lichens on the Red Planet? . Read also article by Professor Chandra Wickramasinghe, May 7, 2016: Evidence of life outside the Earth . In this article Professor Wickramasinghe gives a good view to current situation concerning extraterrestrial life.
In September 2015 the research result about life on early Earth was published: Elizabeth A. Bella, 2015: Potentially biogenic carbon preserved in a 4.1 billion-year-old zircon and UCLA Newsroom October 19 2015: Life on Earth likely started at least 4.1 billion years ago — much earlier than scientists had thought . According to this research life started very soon on Earth. And Earth may have been much cooler in the beginning as we have thought. This report and the observations from Mars both point to direction of panspermia theory. Seeds of life, microbes, were available already in the beginning when our solar system was born. And think about the consequences if panspermia is correct. The mechanism of panspermia has not vanished anywhere. That would mean that interstellar microbes are arriving to the atmosphere of Earth even today. That is an issue which could be observed and which probably has been observed in high altitude sampling experiments by BCAB scientists, read: Milton Wainwright, N Chandra Wickramasinghe, Christopher E Rose, Alexander J Baker 2014, Recovery of Cometary Microorganisms from the Stratosphere . There is also Japanese Tanpopo astrobiology experiment going on onboard International Space Station, trying to observe interplanetary microbes.
The discoveries by Curiosity and Opportunity are changing our view of the Universe. They belong to same series as "Earth is round" and "Earth goes around the Sun". They lead us to answer the question "Are we alone ?". Our Milky Way galaxy may have 100 billion planets in zone of life around their stars. In our solar system we have Earth and Mars in zone of life. And the ocean of Jupiter's moon Europa is also very interesting, as well as the Saturn's moons Enceladus and Titan.
Previously it was thought that the birth of life is extremely difficult and we may be totally alone in whole universe. In 1960s the Drake equation was developed, and then estimate was that we may have 10 civilizations in our galaxy. In 2012 Claudio Maccone made estimate 4590 civilizations , and the closest one could be at 2700 light years distance. After finding life on Mars, and realizing how meteorites may carry life over vast distances, what will be the next estimate for the amount of civilizations?
After reading this article You may have a worry, that can Earth lose major part of its atmosphere as Mars did, especially because of climate change ? Answer is: No. The diameter of Mars is half of Earth's diameter and the gravity is much smaller on Mars (38% of the Earth gravity). Most probably Mars gradually leaked its atmosphere to space because of low gravity, lack of magnetic field and the solar wind. The gravity of Earth is stronger to keep our atmosphere and Earths magnetic field protects atmosphere from solar wind. Another thing is what happens to Earth after one billion years, when our Sun enters next development phase. MAVEN spacecraft by NASA entered Mars orbit in September 2014 to find out more about the reason why Mars lost its atmosphere. In image below Maven results. Distribution of atomic carbon, oxygen and hydrogen around Mars. Clouds of Mars in ultraviolet light