National Geographic : 1977 Jan
"I almost expected to see camels," said a Viking scientist of the windswept, rock-strewn landscape at Chryse Planitia, remarkably similar to deserts on earth. Geologists cata loged an unexpected variety of rocks, from basalts to breccias, from pebbles to a ten-foot- Isfood manufactured? The pyrolytic release (PR) experiment looks for micro organisms which, like plants photosynthesizing on earth, turn carbon gases in the air into carbon-based, organic molecules. Soil is placed in a thumb-size chamber (A). Carbon dioxide and carbon monoxide are added, made of traceable radioactive carbon 14. The soil incubates beneath a lamp that simulates Martian sunlight, minus its ultraviolet rays. Any microorganisms should take up the radioactive gases. The chamber is heated (B) to pyrolyze, or decompose, any microbes present into organic gases. These gases are forced into the organic vapor trap, which lets other gases pass through to a radiation detector for a first count. Higher heating (C) then releases organic vapors so that they, too, escape. If these vapors prove radioactive, they probably come from living organisms. CARBON -14 DETECTOR COUNT BACKGROUND | HEATER RADIATION *~. *Li \su VENT in S' ' re . dii RESERVOIR ' AND INJECTOR ex is CONTINUE COUNT he ADD NUTRIENT it ca de ra ADD SOIL ar B AND INCUBATE th dr CONTINUE COUNT t ADD MORE cc NUTRIENT lo in' .': me th C INCUBATE de 120 HOURS FIRST COUNT HEAT TO -625° C. SECOND COUNT HEAT TO 7000C.