Launching Science: Science Opportunities Provided by NASA's Constellation System

摘要

In 2004 NASA began implementation of the first phases of a new space exploration policy. This implementation effort included the development of a new human-carrying spacecraft, known as Orion; the Altair lunar lander; and two new launch vehicles, the Ares I and Ares V rocketscollectively called the Constellation System (described in Chapter 5 of this report). The Altair lunar lander, which is in the very preliminary concept stage, is not discussed in detail in this report. In 2007 NASA asked the National Research Council (NRC) to evaluate the science opportunities enabled by the Constellation System. To do so, the NRC established the Committee on Science Opportunities Enabled by NASAs Constellation System. In general, the committee interpreted Constellation enabled broadly, to include not only mission concepts that required Constellation, but also those that could be significantly enhanced by Constellation. The committee intends this report to be a general overview of the topic of science missions that might be enabled by Constellation, a sort of textbook introduction to the subject. The mission concepts that are reviewed in this report should serve as general examples of kinds of missions, and the committees evaluation should not be construed as an endorsement of the specific teams that developed the mission concepts or of their proposals. Additionally, NASA has a well-developed process for establishing scientific priorities by asking the NRC to conduct a decadal survey for a particular discipline. Any scientific mission that eventually uses the Constellation System will have to be properly evaluated by means of this decadal survey process. The committee was impressed with the scientific potential of many of the proposals that it evaluated. However, the committee notes that the Constellation System has been justified by NASA and selected in order to enable human exploration beyond low Earth orbit not to enable science missions. Virtually all of the science mission concepts that could take advantage of Constellations unique capabilities are likely to be prohibitively expensive. Several times in the past NASA has begun ambitious space science missions that ultimately proved too expensive for the agency to pursue. Examples include the Voyager-Mars mission and the Prometheus program and its Jupiter Icy Moons Orbiter spacecraft (both examples are discussed in Chapter 1).