Saturday, June 16, 2018

IN SEARCH OF MARTIAN ORGANICS .

The magnificent Viking 2  lander panorama.
This is one the first images
that I remember seeing on TV
.  
Way back in 1976 . I was just 8 years old . The biggest news was that Viking 1&2 landed on Mars , where the first robotic probes ever to land , conduct experiments on another world . It was as big as the Apollo moon landings . I remember reading the National Geographic cover : VIKING 1 ON MARS, (1)>>Getting to Mars still isn’t easy. In the 40 years since the successful Nasa mission, there have been 18 attempts to reach the planet (excluding a joint European Space Agency (ESA)/Russian mission, which is currently en route). US launched the two-part Viking programme in August 1975. Viking 1’s orbiter reached its position on 19 June 1976, and a month later the lander was deployed, successfully reaching the western slope of Chryse Planitia on 20 July. The orbiter operated until 17 August 1980, while the lander operated for over six years. Viking 2 achieved orbit on 7 August 1976, and its lander was deployed on 3 September, reaching Utopia Planitia, on the opposite side of the planet to the Viking 1 lander’s position. The Viking orbiters mapped 97% of the planet’s surface, and its landers and orbiters returned more than 50,000 images. The surface of Mars is currently inhospitable to life as we know it, but there is evidence that the Red Planet once had a climate that could have supported life billions of years ago. For example, features resembling dry riverbeds and minerals that only form in the presence of liquid water have been discovered on the Martian surface.  (2)>>The NASA Viking landers took samples of soil on Mars and tested them for signs of organic carbon. A reinterpretation of the results now suggests the samples did contain organic compounds, but the results were not understood because of the strong oxidation effects of perchlorate, a salt now known to be found in Martian soils. [During their missions, the two Viking landers vaporized Martian dirt and scrutinized the samples for signs of organic - or carbon-based - molecules that could serve as the raw ingredients for life. At the time, all they found were chlorine compounds attributed to contamination, but the new research suggests the Viking probes' heat-treatment may have generated these chlorine compounds from naturally occurring Martian organics, destroying them in the process.?]

Curiosity finds Organics!
Gale Crater as seen by the Curiosity Rover.
An ancient "mud flats" long ago dried up
maybe leaving clues to past
Life.
These are exciting findings, published as twin papers in the journal Science today (June 7). But they aren't proof of life on Mars, or even necessarily strong evidence that there's anything living, or anything that used to be alive, out there. The organic compounds aren't even the first molecules of their kind found on Mars, though they are the oldest.While  NASA always down played [ that they found life]  with any of these Mars announcements , there are certain factors that have  indicate the presense of water on Mars , that something biologic is going on . You have to remember how NASA makes always a  cautious announcement.  The discovery of organic molecules suggests that ancient conditions on Mars may have supported life. We have heard that since the Viking lander days , many "claim" today that Mars had life , was destroyed  in some cataclysmic event . Scientists reported that NASA’s Curiosity rover found large amounts of (3)>>organic molecules in 3.5 billion-year-old rock in an area called Gale Crater. The area on Mars is believed to have once contained a large lake. Now in fact a lake existed in the crater is exciting , that would mean that some residuals could still be there . Back in the 1970s during the Viking landers era , Mars was thought to be a "dead planet" . Things are getting a bit " curious" no pun on the name sake rover that NASA announced that Curiosity also discovered sharp seasonal increases in methane gas in the Martian atmosphere. This could also support the case for life. Ninety-five percent of the methane gas found in Earth’s atmosphere is produced by biological activity. Methane can come from animal and plant life, as well as the environment. So this may not prove "life" , but I must suspect that some kind of "chemistry" is at work on the red planet . So what is mixed up in this soup that produces these results ?  The biologic reaction in the soil chemistry has been inconclusive since Viking , the lated Phoenix lander discovery of  perchlorate chemicals, Perchlorates are reactive chemicals first detected in arctic Martian soil by NASA's Phoenix lander that plopped down on Mars over five years ago in May 2008.It is likely both of NASA's Viking Mars landers in 1976 measured signatures of perchlorates, in the form of chlorinated hydrocarbons. Other U.S. Mars robots — the Sojourner, Spirit and Opportunity — detected elemental chlorine. Moreover, orbital measurements taken by the Mars Odyssey spacecraft show that chlorine is globally distributed.And more recently, NASA's Curiosity rover found perchlorates within Gale Crater, where it landed in August 2012.  If there is water on Mars today it not drinkable for humans , or animal life as we know it , however certain bacteria can thrive in perchlorates .
Remembering Wolf Vishniac--April 22, 1922 – December 10, 1973.
Professor Wolf Vishniac , who would
have found Life on Mars . I was
introduced to him on Sagan's show
"Cosmos" 1979 . We would have
never heard of him with out Carl Sagan's
enthusiasm for Mars.
There was a "chance" that NASA would have found life on Mars a long time ago . NASA has long ago scrubbed the “Wolf trap”, was a life-detection instrument designed by American microbiologist Wolf Vishniac.  Nearly 40 years since Wolf Vishniac's death .Viking mission, which landed on Mars in 1976. Due to budget cuts, it was not included on either lander. The principle of the Wolf trap was to bring martian dust into a tube containing nutrients in liquid form. The instrument would then monitor the state of the liquid; if its pH or cloudiness changed after the martian dust was introduced, this would be an indication of life. One of the members of the EASTEX meeting wondered why no one had devised a remote device to gauge the presence of microbes or organic life, and “challenged the biologists to develop such instrumentation as precursors of instruments to be dropped on the planets to search for indigenous microbiology.” Thus the idea for the “Wolf Trap” was born. According to a history accessible on Solarviews.com, “The very first grant NASA made in the area of biological science was [to Wolf] Vishniac for $4485 to develop ‘a prototype instrument for the remote detection of microorganisms on other planets.’” The website went on describe the objective of the Wolf Trap: “At the heart of the instrument was a growth chamber with an acidity [pH] detector and light sensor; the former would sense the changes in acidity that almost inevitably accompany the growth of
microorganisms, while the latter would measure the changes in the amount of light passing through the growth chamber, (4)>>Microorganisms, such as bacteria, turn a clear culture medium cloudy [turbid] as they grow, and the light sensor would detect such changes. The pH measurement would complement the turbidity measurement, providing an independent check on growth and metabolism.” If used by NASA, this would be the first instrument of its kind on any spacecraft. Its aim was to be placed on a future Mars lander. Since NASA's Curiosity rover landed on Mars in 2012, it has sifted samples of soil and ground-up rock for signs of organic molecules—the complex carbon chains that on Earth form the building blocks of life. Past detections have been so faint that they could be just contamination. Now, samples taken from two different drill sites on an ancient lakebed have yielded complex organic macromolecules that look strikingly similar to kerogen, the goopy fossilized building blocks of oil and gas on Earth. At a few dozen parts per million, the detected levels are 100 times higher than previous finds, but scientists still cannot say whether they have origins in biology or geology. The discovery positions scientists to begin searching for direct evidence of past life on Mars and bolsters the case for returning rock samples from the planet, an effort that begins with the Mars 2020 rover. 

NOTES AND COMMENTS:
(1)>>Getting to Mars still isn’t easy.Let me give you an example. On Mars, the atmosphere is thinner than here. As a result, there is a large temperature difference between the surface and the air. What this practically means, is that if we were standing on Mars our feet and our head would experience different "weather". Amazing, isn't it? Would you imagine your feet having 10 degrees Celcius and your head -20! Now, this fact is back-projected on Earth. First of all, we learn something more for our planet, that the temperature homogeneity that we experience is not a tautology but is a distinct feature of our Earth. But, then a scientist may think "ok, we have a thicker atmosphere, but this doesn't mean that there is absolutely no temperature difference". So, they start measuring it and let's say that they find some small difference.(2)>>The NASA Viking landers took samples of soil on Mars and tested them for signs of organic carbon. Here's some detail about the Viking lander missions that deserves a mention. The two Viking landers each carried 4 different biological experiments to detect life. Amazingly, 3 of the 4 life detection experiments produced a positive result. The 4th experiment which tested for actual organic content of the Martian soil was negative and the scientific consensus was that this meant that organic life could not be present in the soil. However, the recent discovery of perchlorate in the soil on Mars has caused a reevaluation of the experiment which shows that there could have been up to several percent of organic matter in the soil but this would have been destroyed by the heating process of the experiment if perchlorate was also present in the Martian soil. In view of this controversy the official scientific consensus is still that the evidence for life on Mars from the Viking experiments is "inconclusive."No other successful missions to Mars since Viking have contained any experiments designed to directly search for life. Which is a pretty incredible omission really when you think about it. A conspiracy theorist might almost imagine that the mission controllers did not want to public ally settle the question once and for all of whether or not there is life on Mars. Perhaps there are other reasons for the lack of follow up missions to analyse Martian soil directly for life given the intriguing results of the Viking experiments. (3)>>organic molecules. Parts of Mars were capable of supporting life as we know it for lengthy stretches in the ancient past—perhaps hundreds of millions of years at a time, new observations by NASA's Mars rover Curiosity suggest. Since it landed inside the Red Planet's Gale Crater in August 2012, Curiosity has studied a number of different rocks over an elevational range of about 650 feet (200 meters), which represents a time span of tens of millions to hundreds of millions of years.The rovers' analyses indicate that the environment within Gale Crater changed considerably during this period, but never in a way that would preclude life from forming or surviving, mission scientists said during a news conference here at the annual fall meeting of the American Geophysical Union . (4)>>Microorganisms, such as bacteria. It is possible that Life from Earth has been transfered to Mars ? While all spacecraft sent to Mars have to be sterile , It MAY NOT BE the Case . [ see : http://cosmology.com/LifeOnMars.html ] Earth microbes can survive on Mars on certain conditions . Fungi are extremophiles that can survive harsh conditions and environments like deserts, caves or nuclear accident sites.scientists recently reported in the journal Astrobiology. A few of them even managed to cap their year in Mars-like space by reproducing.Although Mars-based life may not use DNA genetic material, then again, it just might. It certainly seems to have worked well for us here on Earth.Even though few of the fungi exposed to Mars-like conditions survived well enough to reproduce, in all cases, at least a fraction did.

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