Sunday, August 24, 2008

Environment

Since our energy problems and opportunities are so intertwined with those of our environment, it’s appropriate to now address what NASA could do for the environment, given additional funding. The main example of NASA contribution to the environment, other than energy-related applications like those suitable for the preceding discussion, is NASA’s Earth observation satellite constellation and Earth observations from space stations. Complementing these efforts are NASA’s scientific investigations of other planets, the Sun, and Earth’s magnetosphere. These efforts allow comparative planetary science studies of the Earth, and allow scientists and operational environment managers to monitor the Earth’s environment in the context of its surroundings.

It is suggested here that in addition to NASA’s existing Earth Observation effort, an additional effort, perhaps on the scale of the $500M to $900M per year, would be appropriate, given the importance of monitoring and understanding our environment. This importance goes beyond the current discussion of global climate change. In fact Earth observation from space contributes countless benefits to citizens, businesses, Federal, State, and Local government agencies, and numerous other organizations. These benefits perhaps rival the practicality of those of the communications satellites, and in fact many of the suggested NASA research and demonstration efforts should be transitioned to the private sector once accomplished. Others should be transitioned to appropriate operational government agencies, such as NOAA, the USGS, or the Defense Department. These transitions will allow NASA to continually expand the research frontier in Earth observation.

Some suggested areas where NASA could contribute to helping us understand and manage the environment follow.

1. Build Proposed Observation Satellites – NASA could address some of the currently unfunded Earth observation missions documented in the National Academies’ Space Studies Board’s document “Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond”. In addition to the inherent environmental science benefit of the Earth Observation measurements these new missions would produce, the additional missions would have a beneficial incremental effect on the launch vehicle and Earth Observation satellite industrial base used by the existing NASA and NOAA environment monitoring missions. For example, the additional launches would present an opportunity for lower per-launch cost for rockets in these mission classes as fixed costs are spread over more missions, as additional launch capacity is available in, for example, EELV-class rockets.

2. Complement Decadal Survey Earth Observations with Planetary and Other Observations – It is suggested that some of the additional environmental satellite funding be directed not on Earth Observation missions, but on Planetary Science and Solar Physics missions selected for their relevance to the Earth’s environment. As mentioned above, Planetary Science missions can serve an important comparative planetary science role in the study of many Earth features, such as climate, weather, atmosphere, cryosphere, volcanoes, geology, and even oceans, to name a few. Solar Physics missions can also shed light on the important effects the Sun has on the Earth’s environment.

3. Build Satellites for Transition to Operational Status – As NASA moves its research satellite capabilities to operational status in NOAA or the private sector, it can smooth this transition by building an additional identical or similar copy of the successful research satellite. This might give the operational organization a chance to learn about the satellite by operating it in orbit, for example, thereby easing the transition as it takes over building new versions of the satellite. This method can also serve as a backup in case of launch or other failure not inherent in the satellite design.

4. Perform Earth Monitoring Demonstrations on the Moon – NASA could address some of the ideas for monitoring the Earth and Sun from the surface of the Moon or lunar orbit described in the document “The Scientific Context for Exploration of the Moon: Final Report” by the National Academies’ Space Studies Board. Additional details on such concepts can be found in the “NASA Advisory Council Workshop on Science Associated with the Lunar Exploration Architecture” at the Lunar and Planetary Institute. Numerous White Papers and slide presentations outlining such concepts can be found, for example, at http://www.lpi.usra.edu/meetings/LEA/. It should be noted that the budget increase in the proposal here for environmental work (as well as all the other application areas) comes at the expense of the Constellation lunar architecture. As a result, concepts that rely on Constellation could, of course, not happen with this proposal. However, this document does NOT propose abandoning the Return to the Moon effort. Instead, it proposes changing it so that it is started with a much more comprehensive robotic effort. In the meantime, the capabilities, infrastructure, and businesses required to implement a sustainable, affordable, and productive lunar return for humans are built. Later, after this foundation is built, humans would return to the Moon. One job that should happen immediately is an effort to demonstrate using robotics various useful things that can be done on and around the Moon, including Earth observations. In many cases, these lunar demonstrations will be useful for monitoring the Earth in and of themselves, but delivering only a small fraction of the benefit that such measurements can bring using larger-scale instruments built and maintained by lunar astronauts. In this way, the robotic and human programs complement, rather than oppose, each other in this proposal. The robotic efforts help show us many of the things we can do even more usefully on the Moon with people. Note that these demonstrations would be, given funding constraints, limited. Use of small, inexpensive, private vehicles like those that may come from the Google Lunar X PRIZE may be warranted in many cases.

5. Use Hosted Payloads - Because of the limited budget, it is recommended that hosting instrument payloads on commercial or international satellites be considered. These approaches strengthen the commercial satellite industry and cooperation with international allies, respectively.

6. Use Suborbital Vehicles - Because of the limited budget, it is recommended that use of low cost suborbital platforms be a considerable part of the added environment monitoring effort. This could take the form of traditional airplane and balloon platforms as well as traditional sounding rockets. It can also take the form of low cost, reusable commercial manned and unmanned suborbital vehicles. These vehicles can allow repeated sampling of the Earth’s middle atmosphere, testing of space-bound environmental satellite instruments and other satellite components, and remote sensing of various features of the Earth for both the benefits of the measurements themselves, and also for calibration reasons for orbiting remote sensing instruments. This approach will also have the benefit of helping the economy through the new suborbital reusable rocket industry, and fostering one important approach to Cheap Access to Space.

7. Use Small Satellites - Because of the limited budget, it is recommended that small satellites be a considerable part of the added environment monitoring effort. A steady series of these lower cost satellites that tend to be less capable but more quickly developed than their larger counterparts can be expected to be a valuable complement to the existing environment satellites. Promoting small satellites also offers a market for smaller launch vehicles, which in turn provide an incentive for an achievable class of economical reusable launch vehicles.

8. Satellite Servicing – It is suggested that the additional environment funding be used as an opportunity to promote satellite servicing capabilities that would benefit future generations of Earth Observation satellites. The servicing could be done by robotic satellites or astronauts. Certainly, since the new funding would be coming from the Constellation program that emphasizes human missions, it would be appropriate to strongly consider satellite servicing by astronauts in many cases. This approach would continue the mutual support advocated here for robotic and human missions. Servicing might involve in-orbit satellite refueling, simple monitoring of satellite external appearance, replacing satellite instruments, batteries, or other components, and tug services to adjust satellite orbits. Tugs might also move satellites to a servicing orbit and location. Such servicing capabilities would require the satellites to be designed to allow easy servicing; this design work could be developed by this new environmental funding. In one of the scenarios hypothesized here, the Ares/Orion vehicles would be made, although probably in downsized form. In both scenarios, commercial space transportation vendors would be prevalent. In the first case, to prevent the NASA Ares/Orion vehicles from competing with the commercial vehicles for International Space Station servicing work, the NASA vehicles would be dedicated primarily to the new astronaut class of LEO satellite servicing missions, and only do ISS work as a backup to the commercial vehicles. Commercial vehicles would gradually move into LEO satellite servicing in this scenario, and ultimately the Ares/Orion vehicles would move entirely beyond LEO satellite servicing to GEO satellite servicing, and later to Lagrange point satellite servicing, gradually passing primary responsibility to commercial vehicles in each step. In the other scenario, the commercial vehicles take on all of these roles over time.

Considering NASA’s potential increased contribution to the environment from these areas combined with some of the other environmentally-relevant application areas described here, NASA has the opportunity to completely transform our understanding and monitoring of the Earth’s environment.

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