An Overview of NASA's Mission to Planet Earth (MTPE)

David P. Radzanowski
Analyst in Aerospace Policy
and
Stephen J. Garber,
Consultant Science Policy Research Division

March 1,1995

95-312 SPR

SUMMARY

Mission to Planet Earth (MTPE) is the National Aeronautics and Space Administration's (NASA) central contribution to the U.S. Global Change Research Program (USGCRP). The MTPE program provides scientific information so policymakers and scientists can formulate strategies to mitigate human impacts on Earth's environment, such as ozone depletion, deforestation, and possible global warming. MTPE includes a constellation of satellites in various Earth orbits: the program's centerpiece known as the Earth Observing System (EOS) and small satellites known as the Earth Probes. The program also includes Landsat 7, ground and aircraft based research, the EOS Data Information System (EOSDIS), and a community of scientists performing research with acquired data from previous or ongoing projects known as phase one missions. The objective of EOS is to acquire a long-term, comprehensive set of environmental measurements about the Earth, particularly those related to global climate change.

In addition, the MTPE program includes data from international Earth observation programs and cooperative projects with Canada, the European Space Agency (ESA), Japan, and Russia. NASA has performed many Earth science programs in the past. This report describes some of the ongoing NASA programs that are considered MTPE phase one missions. EOS and the Earth Probes were new starts in FY 1991, and in 1993 MTPE was taken out of NASA's Office of Space Science and Applications to become a stand alone program office.

For FY 1996, NASA has $1.340 billion available for MTPE. In February 1995, NASA released its FY 1996 budget request; the proposed figure for MTPE is $1.341 billion.

MTPE PHASE ONE MISSIONS

MTPE's phase one missions include several free-flying satellites for global change observations that are the culmination of planning that began in the late 1970s and 1980s. These missions are: the Upper Atmosphere Research Satellite (UARS) that provides data on global ozone change; the TOPEX/Poseidon mission (with France) that is studying ocean circulation; and the Laser Geodynamics Satellite II (LAGEOS II), a joint U.S. and Italian project to acquire information on crustal deformation, continental drift, and ocean tides.(1) A private firm, Orbital Sciences Corp., also is launching a remote sensing spacecraft called SeaStar in 1995 to collect ocean color data. NASA has contracted with Orbital Sciences to purchase data from the Sea-Viewing Wide Field Sensor (SeaWiFS) instrument aboard SeaStar.

EARTH OBSERVING SYSTEM (EOS) AND EARTH PROBES

The Earth Observing System (EOS) is the core space-based segment of the MTPE program. The goal of this long-term program is to collect and make available for analysis a wide variety of data to assess trends in global warming, ozone depletion, and deforestation. The three main U.S. (NASA) contributions to EOS are the AM, PM, and Chemistry spacecraft series. The SeaWiFS instrument aboard SeaStar is to serve as the first EOS-Color mission to examine the ecology of Earth's large bodies of water. If this proves productive, NASA may consider buying more Color data from a private company that would develop, launch, and operate another SeaStar-type spacecraft. Landsat 7, scheduled for launch in 1998, also is considered part of EOS now. In FY 1995 NASA has $591.1 million available for EOS spacecraft, the same amount it is requesting for FY 1996.

Each of the three EOS flight series (AM, PM, and Chemistry) is designed to include up to three spacecraft that would be launched at up to 6-year intervals so that measurements could be taken for each series over an 18-year period. Such an extended time frame is useful to Earth scientists who would like to examine data over a complete solar cycle of 10 to 15 years.

To supplement EOS, NASA plans a series of small satellites called Earth Probes. These satellites will carry instrumentation that requires special orbits or special spacecraft. A table at the end of this report provides details about EOS and Earth Probes spacecraft.

EMS DATA AND INFORMATION SYSTEM (EOSDIS)

The data-handling part of MTPE is known as the EOS Data and Information System. EOSDIS is to provide the processing, storage, and distribution of all data collected by EOS as well as the resulting scientific products. EOSDIS also is designed to have spacecraft and instrument command and control capability, and provide data archive, distribution, and information management of all NASA Earth science data. Many feel that the key to success of NASA's entire MTPE program rests with EOSDIS. While NASA certainly has handled very large amounts of information from space, the vast scale of EOS data is likely to be unprecedented.

EOSDIS is to be an evolving system that is continually updated with new advances in computing and networking technology. NASA believes that this "open architecture" approach will provide flexibility to adapt a system of qualitatively new scale in unforeseen ways. Given this open architecture, a reliable, yet flexible plan for EOSDIS funding is an important consideration.

The first major activity in EOSDIS, known as Version 0, is to develop an experience base for handling large Earth science data sets by reworking existing data sets into more user-friendly formats. Version 0 became operational in September 1994. A working prototype for future EOSDIS versions, Version 0 uses existing scientific networks to link research sites across the country. Interfaces will be developed among nine existing Distributive Active Archive Centers (DAACs) (2) to make multiple data bases available to users in a unified format. By providing the DAACs with the capability to process large amounts of data continuously, it is hoped that investigators will be able to identify new scientific variables of interest so that data collection methods could be changed midstream in the program. The next version of EOSDIS, Version 1, is expected in 1996 after the Tropical Rainfall Measuring Mission (TRMM) is launched and begins collecting data.

NASA has $230.6 million available in FY 1995 for EOSDIS. For FY 1996, NASA is requesting $289.8 million for EOSDIS.

SUMMARIES OF SOME KEY ISSUES RELATED TO EMS AND EOSDIS:

Cost of EMS

In its original configuration, EOS included two series of polar orbiting spacecraft platforms called EOS-A and EOS-B. Each was to have 10-16 different instruments and was to be replaced every 5 years to achieve a 15-year mission lifetime. Initially, EOS was estimated to cost $17 billion through FY 2000. During 1991 and 1992, NASA responded to growing concerns about the high cost of EOS by breaking up the EOS-A and EOS-B platforms into several smaller spacecraft and by streamlining management and technical configurations. In mid-1992, NASA estimated that the reconfigured EOS program would cost approximately $8 billion through FY 2000.

In fall 1994, NASA took several steps to trim the EOS and EOSDIS program budget through FY 2000 by approximately $750 million to a total of $7.25 billion in response to Federal budget constraints. The EOS-Altimetry mission was split into Laser and Radar components and the Radar Altimetry segment was cost capped. (The chart at the end of this report provides further details.) By delaying the purchase of certain EOSDIS computer equipment until the technology is more mature, NASA believes it can save money. Reconfiguring payloads also will enable EOS spacecraft after EOS-AM1 to be launched on Delta expendable launch vehicles, instead of the larger and more expensive Atlas rockets.

Although NASA has reduced the cost of EOS and EOSDIS from $17 billion to $7.25 billion through FY 2000, many observers believe that NASA will not have sufficient resources to fund EOS and EOSDIS at their current predicted levels given NASA's overall budget. While NASA has not released an estimate of the total program cost, the currently projected 18 year operational lifespans for each spacecraft series imply that $7.25 billion would be only a fraction of the total runout cost. Once several EOS spacecraft are collecting data after 2000, the operating costs of EOSDIS will likely rise while NASA continues to develop other EOS spacecraft. In an era of constrained budgets, there is concern that in the future NASA may not have sufficient funding for several large programs such as EOS and EOSDIS, the Space Shuttle, the Space Station, and space science.

Complexity of EOSDIS

Outside of NASA, EOSDIS has been the subject of some controversy. In January 1994, the National Research Council (NRC) released an independent review that found fault with the overly centralized nature of EOSDIS, noting that such an approach was risky, inflexible, and unresponsive to its users. Although this report did not take into consideration changes that EOSDIS managers made in the fall of 1993, NASA made further modifications to address the NRC's criticism. In addition, a 1992 Government Accounting Office (GAO) report, Earth Observing System: NASA's EOSDIS Development Approach is Risky, stated that EOSDIS Version 0 did not adequately foster development of the advanced technologies that will eventually be required by EOSDIS. NASA believes that the open architecture of EOSDIS directly allays the GAO's concerns.

Usefulness of EOS Scientific Data

Some scientists have suggested that because Earth system science is such a young and broad field, a wide variety of multi-purpose instruments should be included on EOS so that various measurements can be made to pursue unforeseen paths of inquiry. Some scientists even feel that it is difficult to formulate certain relevant scientific questions. EOS critics, however, object to spending large sums of money for EOS when its objectives do not seem to be defined clearly. EOS managers, however, argue that they have established clear scientific priorities. Advocates also argue that it is science's charter to explore untapped areas of knowledge, especially in relatively new disciplines such as Earth system science.

Viability of Privatization

The issue of privatization or commercialization cuts across many of NASA's space activities including MTPE. Despite the many commercial uses for remotely sensed information, the Government is still the largest consumer of complex scientific information such as MTPE data. With launch vehicle and spacecraft development costs still high, it is difficult for private firms to recoup their investments by selling data that their spacecraft collect. Thus few private businesses have built and launched scientific spacecraft without Government support. While the future cost of access to space potentially could be significantly reduced by using new launch vehicle technology, this is probably 10 to 15 years away. Moreover, it likely will take a considerable amount of time before industry is willing to undertake technical projects with such high financial risks as building and launching spacecraft without significant Government support.

Pricing of Data

Current U.S. Government policy is that EOS and USGCRP data shouldn't cost more than the marginal cost of reproduction for the user. In considering whether to institute user fees, policymakers will likely evaluate whether a billing system would be cost effective for small orders and whether casual users might take advantage of the system by requesting frivolous amounts of data. In addition, the various international participants may need to coordinate their data policies in terms of granting researchers from all countries equal access to equivalently priced data from all instruments. Some European nations have proposed distributing EOS data on a partially commercial basis, while the U.S. is inclined toward providing freedom of access to data.

SUMMARY AND FUTURE OUTLOOK

While the Clinton Administration and many outside observers believe that environmental programs should be a high priority for both the Nation and for NASA in particular, the Republican-controlled 104th Congress may undertake a rigorous examination of MTPE. Chairman Robert Walker of the House Science Committee reportedly has stated that although NASA's budget should keep pace with inflation, the MTPE program will be scrutinized carefully for potential cost savings.(3) In January 1995, the White House directed NASA to cut its budget by $5 billion over the next five years, and it may be difficult for MTPE to continue to fund an EOS program that is to cost $7.3 billion through the year 2000. Despite various restructurings of EOS, many analysts are still concerned about the size and structure of EOS and EOSDIS. Yet many scientists are excited about the potential new discoveries that could be possible through international cooperation on a truly global issue such as the environment.

Earth Probes* and EOS Spacecraft

Endnotes

1. UARS was launched in Sept. 1991, TOPEX/Poseidon was launched by the European Space Agency (ESA) in Aug. 1992, and LAGEOS II was launched by the Space Shuttle in Oct. 1992.
2. The current DAACs are: the Alaska Synthetic Aperture Radar (SAR) Facility; the Earth Resources Observation System (EROS) Data Center; the Consortium for International Earth Science Network; NASA's Goddard Space Flight Center DAAC; NASA's Langley Research Center DAAC; the Oak Ridge National Laboratory; NASA's Marshall Space Flight Center/University of Alabama DAAC; the National Snow and Ice Data Center; and NASA's Jet Propulsion Laboratory (JPL) DAAC. There is a related Data Processing Facility in Fairmont, WV.
3. Ferster, Warren. House Panel May Target Mission to Planet Earth, Space News, Dec. 19-25, 994 p 3.