Viking missions

With the naked eye, ancient people could discern that the planet Mars is red, just as is the calx of iron ( rust )- Associating Mars—the god of war—with iron—the stuff of weapons, as well as with hlood—is intuitively reasonable. Late twentieth-century business executives wore red power ties to meetings. But in an almost too wonderful confirmation of ancient intuition, the findings of the NASA Viking Mission, which landed two spacecraft on Mars in 1976, indicated a red surface composed of oxides of iron eyeball chemical analysis by the Ancients at over 30 million miles—not bad ... 

NASA s Viking Mission Two Laboratories on the Surface of Mars... 

As mentioned earlier, analytical separation devices based on GC instrumentation have already been used in various space applications such as atmospheric probes and surface landers. Table 17.1 contains a summary of planetary exploration missions by NASA (both atmospheric probes and landers) where GC instrumentation has been used. The Viking mission to Mars contained two landers equipped with various scientific instruments for in situ analysis of the Martian atmosphere and soU. One of the analytical devices utiUzed a GC with one packed column equipped with a TCD to analyze the gases released by the soil (the Gas Exchange experiment GEX) after digestion of a nutrient liquid. The... 

RBS can provide absolute quantitative analysis of elemental composition with an accuracy of about 5%. It can provide depth-profile information from surface layers and thin films to a thickness of about 1 pm. In some cases, however, the high-energy beam can damage the surface. This is particularly a problem with insulating materials, such as polymers, alkali halides, and oxides. The Mars Pathfinder mission in 1997 contained an alpha proton X-ray spectrometer (APXS). In its RBS mode, the spectrometer bombarded samples with alpha particles and determined elemental composition via energy analysis of the backscattered particles. In addition to RBS, the APXS instrument was designed to carry out proton emission and particle-induced X-ray emission (PIXE) experiments. Soil and rock compositions were measured and compared to those from the earlier Viking mission. 

Figure 1.1 is an actual mass spectrum of the Martian atmosphere (after removal of CO and CO2) from the US-NASA Viking mission. 

For more details the reader is referred to Carr and Head, 2010 [59], There is evidence for recent water flows on Mars based on geologic maps from the Viking mission that indicate geologic and hydrologic activity extending into the Late Amazonian epoch especially in the Tharsis and Elysium area. Examples for such evidence are... 

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