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Toward a Microgravity Research Strategy (Chapter 4) Toward a Microgravity Research Strategy 4 Toward the Development of a Research Strategy The Committee on Microgravity Research recommends that a longterm research strategy, such as that developed by each of the Space Studies Board's other discipline committees, be developed for microgravity science. The strategy should be based on the following considerations: 1. It should be recognized that, to date, no examples have been found of materials that arc worthy of manufacture in space. Unless and until such examples are found, space manufacturing of products to be used on Earth should be deemphasized as a reason for undertaking microgravity research. The descriptor "materials processing" should not be used for NASA's REPORT MENU budget line item because it is misleading. The CMGR recommends that NOTICE "microgravity research" be used instead. MEMBERSHIP SUMMARY 2. The main rationale for the microgravity research program should be to CHAPTER 1 improve our fundamental scientific and technological knowledge base, CHAPTER 2 particularly in areas that are likely to lead to improvements in processing and CHAPTER 3 manufacturing on Earth. A secondary rationale should be to develop the CHAPTER 4 technologies for handling materials in space and possibly for processing APPENDIX A materials to be used in space. APPENDIX B APPENDIX C APPENDIX D 3. The g-level (acceleration vector environment) must be measured APPENDIX E accurately, locally, frequently, and synchronously with every experiment. These APPENDIX F data must be provided to each principal investigator immediately. 4. Experiments that appear to have produced promising results should be repeated to examine reproducibility. Most results to date are the product of single experiments. 5. A number of examples illustrate clearly that microgravity makes a measurable difference. The question is: Why? Critical experiments should be file:///C|/SSB_old_web/cmgr92ch4.htm (1 of 4) [6/18/2004 11:09:24 AM]

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Toward a Microgravity Research Strategy (Chapter 4) designed and conducted to learn why certain phenomena occur in microgravity, not merely to exhibit that they do occur. 6. A thorough program of ground-based research must precede and succeed every microgravity flight. Much of this research will form a context for the flight program but will not be directly related to a flight experiment. Such a context is very important because of the high relative cost of flight experiments. Points 7 to 9 below pertain to this ground-based program. 7. Much more effort needs to be made to model phenomena suggested by microgravity observations. In many cases, models are obsolete (e.g., for eutectic growth) or nonexistent (e.g., for protein crystal growth). 8. The materials used in microgravity experiments should be characterized thoroughly both before and after flight. The thermophysical data needed to interpret experiments should be measured as a part of the program if they are unavailable from the literature. 9. Whenever exemplary materials are produced in microgravity, considerable effort should be made to replicate them through Earth-based research, which is much less expensive and might lead to commercial applications. 10. The interest in electronic materials today is in thin films; bulk electronic materials are of secondary importance and should be studied in microgravity only if their quality as substrates or primary components is important or to the extent that such studies can yield fundamental knowledge about processing. 11. Research opportunities should involve a planned budgeted balance of focused opportunities, some communicated by an Announcement of Opportunity (AO) from NASA and others funded on the basis of unsolicited proposals submitted to NASA. The field is still very young, and so many good ideas are yet to come. If AOs are used to distribute too much of the funding, growth of the best ideas will be stifled, and the field will not be intellectually exciting to the scientific community. 12. The funding level for research and analysis in microgravity science should be established as a fixed percentage of the total program of NASA's Microgravity Science and Applications Division in order to build a strong scientific base for future experiments. 13. NASA and its advisory committees should analyze and classify experiments according to their minimum facility requirements so that they can be carried out in the most cost-effective manner. From this classification, candidate experiments for drop towers, free-falling aircraft, sounding rockets, the Space Shuttle, space stations, or free-flying spacecraft can be identified. file:///C|/SSB_old_web/cmgr92ch4.htm (2 of 4) [6/18/2004 11:09:24 AM]

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Toward a Microgravity Research Strategy (Chapter 4) 14. Most microgravity equipment should accomplish specific experiments and should be designed and built in close cooperation with the principal investigator(s). The designing and building of multiuser facilities for anticipated experiments should be avoided. 15. The centers for the commercial development of space should be reviewed technically to ensure their quality and to ascertain to what degree their original mission of becoming independent through industrial funding has been accomplished. Based on the above points, a strategy for microgravity research should include: 1. A definition of the overall goals of the microgravity science field; 2. A summary of the current knowledge that is related to strategic considerations; 3. A statement of the fundamental questions that need to be answered; 4. The overall strategy and its rationale, derived from and based on the fundamental questions and the ability to address them; 5. The primary scientific objectives ranked in order of their priorities (together with the value criteria used); 6. A set of experiments required to achieve the stated objectives; 7. Definition of the requirements for such experiments and their accommodation in various facilities and low-gravity experiment modes, which reduces total cost and enhances the productivity of experiments; 8. Other resources needed for a successful scientific program, such as access to space, operational support, and ground-based research; 9. The indicators for a successful scientific program, for example, comparison with accomplishments attained during ground-based equivalents of experiment time, equipment utilization, and so on. file:///C|/SSB_old_web/cmgr92ch4.htm (3 of 4) [6/18/2004 11:09:24 AM]