Final answer:
The analysis of martian surface samples has revealed the exciting presence of water and organic (carbon-based) compounds. This discovery hints at the possibility that Mars may have once had the environmental conditions to support oceans and perhaps life. Features like mudcracks, as well as the findings from the Viking experiments and various Mars rovers, support this hypothesis.
Step-by-step explanation:
One of the most exciting results from analysis of martian surface samples has been the discovery of water and organic compounds. The presence of these substances suggests that Mars may have once harbored oceans and potentially even life. Analysis of martian samples shows evidence of flowing water in Mars' distant past, and certain features such as mudcracks found in Gale crater support the theory that liquid water was once prevalent on the planet's surface.
The discovery of organic (carbon-based) compounds in martian materials has been particularly intriguing. Although meteorites from Mars have landed on Earth, allowing study of martian material, in situ analysis by rovers like Spirit, Opportunity, and Curiosity has provided direct evidence of paleolakes and past environmental conditions that could have supported life.
However, it's important to note that while the Viking spacecraft soil tests showed chemical activity, it was not indicative of life. Instead, this activity was likely due to chemical reactions from water being added to the soil, showing that martian soil is chemically active due to solar ultraviolet radiation exposure.