Tuesday, August 26, 2008

Assessment of Goals

Now a short amount of justification is given to show that each of the goals can be achieved with the previous proposal.

1. Be relevant; address problems whose solution is important to the nation. – By focusing NASA’s new efforts on application areas that are important to the nation based on common sense judgment and by actual government spending levels, the efforts should be relevant. In contrast, Constellation attempts to solve problems that are not obviously relevant or important to the nation (at least until additional lunar robotic demonstrations are performed and commercial infrastructure capabilities are developed) such as a government Heavy Lift Vehicle and a variant of Apollo.

2. Promote commercial space and international cooperation. – Commercial space is promoted by the increased attention to buying commercial services, hosted payloads, COTS and similar efforts, innovation prizes, progressively handing off human space capabilities like LEO access, LEO satellite servicing, and so on to commercial space, and development of advanced technology useful to commercial space, but not being funded by commercial space research and development. International cooperation is much easier to arrange with the small programs envisioned and emphasized here, such as suborbital spaceflight and small robotic space missions. International cooperation is already common on robotic space science missions. The restrained human Exploration mission plan outlined here almost requires international cooperation to achieve timely results. In contrast, Constellation is run by NASA rather than commercial space, and it involves no international cooperation. Any commercial space or international cooperation add-ons to Constellation are relegated to some vague and unspecified time in the distant future.

3. Encourage “Cheap Access to Space (CATS)”. – This plan emphasizes numerous small, focused CATS efforts, as well as larger COTS efforts that may move towards CATS, in the Transportation application area. The plan also encourages CATS through NASA purchase of commercial suborbital space services. These purchases will give incentives to develop more capable suborbital vehicles, as some NASA applications will require greater altitude, repeated testing, or more payload mass or volume. The plan also opens space markets that should encourage CATS, such as space station work, traditional communications satellite applications, environment satellites, planetary science missions, and more. Small missions are encouraged in those cases that are run by NASA, resulting in more frequent launches, sized appropriately for reusable launch vehicles, per funding dollar. Finally, the plan promotes NASA innovation prizes. It is expected that suborbital and orbital CATS capabilities would be the subject of many of these innovation prizes. In contrast, Constellation involves an expensive pair of NASA rockets. The launch cost per pound of the large Ares V compared to small, frequently used CATS vehicles can of course be debated; it is possible that the CATS capabilities that result from this effort would not match the per-pound capabilities of Ares V. It is suggested here that even if this is the case, the smaller rockets are more useful in a productive CATS sense. In addition, the markets and capabilities developed by this plan (possibly including reusable launch vehicles, useful lunar surface applications demonstrated, tugs, and space refueling) would make it easier to demonstrate a need for an HLV (if one exists), and make it easier to develop the HLV much later when its time may come.

4. Address the central goals of the VSE: Security, Economics, and Science. – This plan addresses Security head-on with its Defense and Security application area, and complimentary areas like the Environment application area’s Earth observation missions, the Transportation application area’s COTS and CATS efforts, satellite servicing efforts, suborbital spaceflight business, and more. It addresses Economics through a strong and comprehensive commercial space orientation, development of space infrastructure and other economically useful capabilities, emphasis on economically-useful science like Earth observations, and education of a space workforce. It emphasizes science in the Environment application area, aspects of the Exploration application area in the near term (exploring Earth’s oceans) and long term (exploring asteroids and/or the Moon), support for science research in the Education area, and robotic probe capability improvements and demonstrations in several areas. In contrast, Constellation offers little to the Security, Economics, and Science areas. If Constellation is successful, there may be some important science done after the human lunar missions start, but that is many years away, and highly speculative. Economic benefits of Constellation in the long term are even more speculative. This is in part due to the nature of lunar exploration, which requires more robotic demonstrations and surveys, CATS, space infrastructure, and commercial space capability to provide the technical and business foundation, as well as the rationale for the program. Constellation only addresses one part of the foundation needed, the space transportation part, and it does this on a risky, long schedule with an overly large budget. It has also been suggested that the Ares V rocket could provide useful capabilities for Security and Science. It is argued here that Security and Science needs are more aligned with responsive, cost-effective, and smaller rockets, space infrastructure, suborbital vehicles, and responsive commercial attitudes. Even the Titan launcher was too expensive for Defense applications, and was cancelled.

5. Develop useful space infrastructure. – This plan attempts to build a Cheap Access to Space infrastructure through NASA commercial buys, prizes, COTS, X planes, and similar efforts. It supports improving the International Space Station and encouraging additional space stations through NASA ticket purchases and other commercial arrangements. It promotes satellite servicing, including tugs, refueling, and maintenance capabilities. Instead of NASA developing these capabilities and keeping them, the model used is for NASA to either encourage commercial space to develop them, or for NASA to develop them and then pass them over to commercial space (purchasing the services if they are appropriate for NASA’s needs). In contrast, Constellation avoids developing useful space infrastructure. The Constellation space transportation system is largely or entirely discarded after each mission. In the distant future, lunar habitats may be built, but the usefulness of these habitats is severely restricted by the non-existence of the other space infrastructure that should come before the lunar habitats, like CATS, tugs, refueling, multiple space stations, and routine LEO and GEO space transportation.

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