Of the studies listed above, the three that did not result in final reports were the Big Bang Observer, the Innovative Interstellar Explorer, and the Titan Organics Exploration Study. For the incomplete Innovative Interstellar Explorer mission study, the committee received a briefing that focused primarily on the science and the changes to the mission profile that could result from use of the Constellation System. The committee received briefings on and addressed the two Neptune mission studies in a single assessment.
The National Research Council’s (NRC’s) Committee on Science Opportunities Enabled by NASA’s Constellation System asked the principal investigators or other representatives of the 14 Vision Mission studies to present their studies to the committee at its first meeting, on February 20-22, 2008. The principal investigators were asked to consider how their existing studies might benefit from the Constellation capabilities—primarily the larger payload capability and shroud dimensions of the Ares V rocket and the possibility of the human servicing of spacecraft. Because of the scheduling requirements of the committee’s work, the presenters had only limited time to assess how the Constellation capabilities might affect their proposals. Some indicated that the Constellation System would have no appreciable effect on their concepts, and others indicated that it would serve as a substitute for required technology development. Some of the proposers also indicated that their science objectives might be enlarged and expanded if they had additional mass and volume available.
In its interim report, the committee evaluated the 11 Vision Missions on which final studies had been completed.3,4 The committee also issued a request for information to the scientific community seeking proposals for additional space science missions (see Appendix C in the present report), resulting in 6 additional mission proposals:
Advanced Technology Large-Aperture Space Telescope (ATLAST),
Dark Ages Lunar Interferometer (DALI),
8-Meter Monolithic Space Telescope,
Exploration of Near Earth Objects via the Crew Exploration Vehicle,
Solar Probe 2, and
Super-EUSO (Extreme Universe Space Observatory).
For its final report, the committee evaluated these 6 additional mission concepts using the same criteria used for the Vision Mission studies.
National Research Council, Science Opportunities Enabled by NASA’s Constellation System: Interim Report, The National Academies Press, Washington, D.C., 2008.
For the interim report, and for this final report, the committee chose to consider both the Vision Mission final reports and the presentations made to the committee during its February 2008 meeting. In some cases there were no or only minor differences between the reports and the presentations. In others, the differences primarily concerned speculation supported by limited analysis on how the mission would benefit from the Constellation capabilities. For the Interstellar Probe concept, the presentation was made by the team that did not produce a final report. However, the science objectives of both Interstellar Probe studies were identical, and the presenter focused primarily on how the mission concept would benefit from the Constellation System.