The device that might have first detected life on Mars — a complete NASA VIKING Lander Biological Instrument (VLBI) : 無料・フリー素材/写真
The device that might have first detected life on Mars — a complete NASA VIKING Lander Biological Instrument (VLBI) / jurvetson
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
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| 説明 | And this is the only complete flight-ready unit remaining on our planet. The first successful landers on Mars, Viking 1 and 2, conducted four separate experiments to look for signatures of life in the Martian soil. This VLBI housed three of them, and I have the fourth (the Gas Chromatograph Mass Spectrometer CGMS) displayed next to it. TRW electronics modules are on the right in green, soil distribution assembly in the cylinder below the collection flower, and the lid is lifted on black spacers above the Bio experiments to give a peek to the incredible complexity inside.The GCMS found no carbon compounds, even less than on the moon. This was heartbreaking. It seemed to trump the results of the VLBI experiment that had a positive result: the Labeled Release (LR) experiment, in which something metabolized a radioactive carbon-14 laced nutrient soup fed to the Martian soil, releasing that carbon-14 as a gas, like CO2. Perhaps you recall the deflating results, popularized in the 70s, of Mars as a lifeless planet.But some of the VLBI engineers believed that the signature of life had been found if the GCMS reading was erroneous and even had a theory as to why - perchlorate in the soil, heated up in sample prep in the GCMS, could destroy all carbon signatures in the test configuration. Many years later, it was discovered that perchlorate is abundant in the Martian soil, leading some scientists in 2012 to reverse the conclusions reached in 1976. (including the “Mars Czar” at the time, Scott Hubbard, who spoke with me about this with great excitement). “The new study of the Viking program’s finding was initiated after the August 2008 discovery of perchlorates in Martian soil by the Phoenix lander. Perchlorates are salts whose powerful oxygen-busting capacity tends to combust organics. The Viking team had no reason at the time to think Martian soil was perchlorate-rich, so the tiny trace chemicals they found in the Viking experiment were dismissed as contaminants from Earth. The new study asserts that they were combusted organic compounds, fingerprints of carbon leftover from contact with perchlorates in the soil. Viking’s failure to find organic compounds was the main argument against sending further missions to Mars to seek them” (PopSci)"The designer of the VLBI-LR experiment, Gilbert Levin, believes the positive LR results are diagnostic for life on Mars. According to Levin and Patricia Ann Straat, investigators of the LR experiment, no explanation involving inorganic chemistry as of 2016 is able to give satisfactory explanations of the complete data from the LR experiment" — WikipediaAnd then, in 2018, the Curiosity rover found myriad organic molecules at the surface (counter to the Viking CGMS finding), and long-term atmospheric sampling found “low levels of methane within Gale Crater repeatedly peak in warm, summer months and drop in the winter every year.” And now, in 2021, we have found organic salts in the Martian soil, to NASA's excitement: “A team of NASA researchers suspect that they’ve made a huge discovery about Mars: organic salts on the surface. If that’s true, then it would lend much more credibility to the hypothesis that Mars once supported life.” Perhaps it is time to revisit the original data, and see if different conclusions might be drawn — most likely inconclusive at this point — but potentially motivating for experiments to come.The top of the unit houses the stainless steel ‘flower’ receptacle which received Martian soil samples deposited by the robotic scoop on the Viking. After receiving the sample, it could be heated to different temperatures and passed through a column into a lower chamber where the sample would be distributed into one of three experiments. All parts are present and connected as they were when this unit was readied for a Mars mission at NASA Langley, the headquarters for the Viking biological research group. Two Viking landers carried three types of biological experiments to the Martian surface in the late 1970s to look for any evidence of life on the planet. As the two landers were identical, the same three experiments were carried out in different locations. Despite the successful completion of all the experiments, no traces of any organic compounds were found on the surface, and the general scientific community declared that Viking’s biological tests were inconclusive. However, in 2012, the data from the LR Experiment was re-analyzed and some scientists believe it may have indeed detected life.I also did a recent video overview of the Viking Lander Biological Instrument (VLBI) and GCMS. All part of the Future Ventures’ 🚀 Space Collection. |
| 撮影日 | 2021-02-24 15:00:43 |
| 撮影者 | jurvetson , Los Altos, USA |
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| カメラ | DSC-RX100M3 , SONY |
| 露出 | 0.017 sec (1/60) |
| 開放F値 | f/2.8 |