Intensive, programmatic studies of missions being directed to specific locations in the solar system can seek to identify the most efficient means of exploration, the pathway that would provide the greatest amount of decisive information in return for the simplest, quickest, and cheapest measurements and analyses. Such studies inevitably reflect diverse factors. The task group’s purposes in this study are to focus on organic matter rather than on specific missions or locations, to call attention to objectives of particular importance, and to consider issues that might cut across otherwise-separate programs. To accomplish this, the task group set out to address the following questions:
What are the sources of reactants and energy that lead to abiotic synthesis of organic compounds and to their alteration in diverse solar system environments?
What are the distribution and history of reduced carbon compounds in the solar system, and which features of that distribution and history, or of the compounds themselves, can be used to discriminate among synthesis and alteration processes?
What are the criteria that distinguish abiotic from biotic organic compounds?
What aspects of the study of organic compounds in the solar system can be accomplished from ground-based studies (theoretical, laboratory, and astronomical), Earth orbit, and planetary missions (orbiters, landers, and sample return), and which new capabilities might have the greatest impact on each?
With these questions in mind, the task group sought to identify reservoirs of organic material in the solar system and to consider what is known about their history as well as their present composition. Two broad questions can be identified:
What are the relationships between organic materials in diverse extraterrestrial settings such as planetary and satellite regoliths, asteroids, comets, and meteorites?
What processes produced the organic materials?
Much can be inferred from compositional and isotopic data. For example, a particular set of organic compounds might be found in interstellar media. The same materials might occur in comets, and plausibly related materials could turn up in meteorites and on asteroids. The pattern would indicate a possible line of inheritance, showing that, at the time of its origin, the solar system incorporated interstellar organic material. The hypothesis could be