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Appendix D: Current NASA and DoD Small Spacecraft Programs NASA Programs Both JPL and GSFC have programs underway involving the use of small spacecraft. JPL is the lead center on the Mars Pathfinder mission, which is projected for launch in 1996. The Mars Pathfinder mission is one of the Office of Space Science's Discovery missions which represents an entire class of smaller, less expensive, and more frequent science missions. All of the various DroDosed Discoverv missions are intended to proceed from development to flight in three years or less at a clevelopment cost of less than $150 million. Contingent on funding, Discovery missions are planned for launch at a rate of one every two years (David, 1993; McCarthy, 19931. JPL has proposed the Pluto Fast Flyby mission, which is a mission to the last unexplored planet, Pluto. The goal is to launch two small spacecraft of less than 140 kilograms each on a direct trajectory to Pluto by 2001. The total estimated mission cost is $400 million plus launch. The severe limitations imposed on spacecraft mass and cost demand technological resourcefulness and an innovative approach to program planning (StaehIe et al., 1993)a JPE also assisted the BMDO with the first MSTT spacecraft that was launched in 1992 The MST} program is designed to test miniature sensor technology. MSTI-I! was launcher! in May, 1994, and MSTI-TII and MSTI-IV are scheduled for launch in late 1994 and early 1995, respectively. MST! V has been transferred to the Air Force and reduced to component development, ant! MST! V! has been cancellecI. The GSFC small spacecraft effort is an extension of the long-stancling Explorer and Small Explorer programs, while JPL small spacecraft efforts are of more recent · ~ orlgln. In 1988, GSFC initiated the Solar, Anomalous' and Magnetospheric Particle Explorer project, which was successfully launched in 1992. This mission was the first in the Small Explorer program. Two other Small Explorer missions that have been approved are the Fast Auroral Snapshot Explorer, to be launched in 1994, and the Submillimeter Wave Astronomy Satellite to be launched in 1995. These ongoing efforts predate the recent enthusiasm over small spacecraft and signify the continuing ability of small spacecraft to contribute to focused scientific research as they have for decades. These projects require competitive selection of experiments and peer review. A NASA 124
Appendix D Announcement of Opportunity has also been issued for the Middle-Class Explorer mission, which uses somewhat larger spacecraft of approximately 450 kilograms, at a cost of around $75 million, to be launched on a Taurus-cIass expendable launch vehicle. In addition, GSFC has a role in the first Discovery mission, the Near Earth Asteroid Rendezvous. This program received new-start funding in the fiscal year 1994 budget and is scheduled for launch in 1996. The Near Earth Asteroid Rendezvous spacecraft will be built by the Johns Hopkins University's Applied Physics laboratory. GSFC also is responsible for the Total Ozone Mapping Spectrometer series of spacecraft. The first Total Ozone Mapping Spectrometer spacecraft is currently being built by TRW and is scheduled for launch in 1994. NASA also is proposing the TIMED mission, which includes a system of probes to study little-known aspects of the Earth's upper atmosphere. TIMED is to be the first of the Office of Space Science's series of small spacecraft missions that are known as the Solar Terrestrial Probes. The TIMED mission features a strong emphasis on new technology insertion to reduce mass. In support of the NASA Administrator's recent efforts to promote missions with lower cost, faster development and launch time, and higher tolerance for risk, while enhancing productivity and economic competitiveness, the Spacecraft and Remote Sensing Division was created within OACT at NASA Headquarters. This division is responsible for the development of technology to reduce the cost ant! launch weight of spacecraft through exploitation of miniaturized components, advanced instrumentation, operations technology, and sensors integrated into advanced design concepts. The Spacecraft and Remote Sensing Division is currently working with the Office of Space Science to develop and infuse advanced technology into three scientific small spacecraft missions: (~) the proposed TIMED mission, (2) the Mars Pathfinder mission, and (3) the proposed Pluto Fast Flyby mission. For the proposed TIMED mission, OACT is funding i} technology items, which include attitude and navigation sensors, power-system components, science instrument components, cryocoolers, thrusters, and lightweight structures. For Mars Pathfinder, OACT is funding the rover clevelopment, and for the proposed Pluto Fast Flyby mission, OACT is actively funding 12 technology items, which include attitude and navigation sensors, lightweight structures, communication and propulsion components, and high-density packaging. Sixteen additional items are currently under consideration for future funding (NASA/OACT, 1993). In addition to the technology infusion activities q OACT's Spacecraft and Remote Sensing Division has established a Small Spacecraft Technology Initiative. This program will demonstrate a new approach to technology integration, resulting in two technology demonstration flights within three years and designed to envelope a range of mission requirements and develop standard hardware and software interfaces for various applications. A Request for Proposal for the Small Spacecraft Technology Initiative was released February 28, 1994, with awards scheduled for announcement in the second quarter of 1994. Programmatic and budget details of the Small Spacecraft Technology Initiative are discussed further in Appendix A. NASA is currently involved in several joint spacecraft programs, such as the Deep Space Program Science Experiment, also known as the Clementine mission with 125
126 Technology for Small Spacecraft BMDO, that was launched in January, 1994. The ~ 15-kilogram, $50 million Clementine spacecraft was built by the Naval Research Laboratory en c! is flight testing several critical small spacecraft technologies and instruments during its orbit of the moon and subsequent asteroid rendezvous (Schaub and Regeon, 1993~. NASA was also working with ARPA on the now-cancelled Collaboration on Advanced Multispectral Earth Observation (CAMEO) spacecraft that was scheduled for launch in 1997 to demonstrate dual-use technologies for civilian and military applications (Davis and ImIer, 1993~. DoD Programs Although civilian and military space budgets today are roughly comparable, for the last decade, DoD spending on space programs has consistently exceeded] the civilian space budget, sometimes by as much as 50 percent (U.S. Space Policy Advisory Board, 1992~. Within the framework of its distinct missions, DoD space programs have also faced many of the same technology imperatives as NASA, striving for improved performance at reduced cost. As a result, NASA now stands to benefit in the near term from many of the initiatives undertaken by DoD over the last several years. DoD- sponsored programs have produced a broac} range of valuable hardware, from component technologies to entire spacecraft and launch vehicle systems. Over the last four years, ARPA has conducted over 50 projects under its Advanced Space Technology Program to reduce the risk and cost of future spacecraft systems. Projects have included investment in the Pegasus and Taurus small spacecraft launch vehicles, small spacecraft demonstrations with the Microsat and DARPASAT programs, and a number of advanced spacecraft subsystem technologies with the goal of increasing payload mass fraction (Nicastri, 1993~. ARPA is involved in the joint Technology for Autonomous Operational Survivability (TAOS) program with the U.S. Air Force to demonstrate advancer} technologies and operational concepts (Davis and Imier, 1993~. The Technology for Autonomous Operational Survivability spacecraft was successfully launched along with an ARPA spacecraft on the Taurus launch vehicle March 13, 1994. This was the first launch of the U.S. Air Force's Space Technology Experiments Program series of advanced technology spacecraft. BMDO has also made significant investments over the past several years in miniaturized and lightweight technology programs to support the Brilliant Eyes and the now-cancelled Brilliant Pebbles programs. For instance, the MSTI program is designed to test lightweight sensor technology; the I ightweight Exo-Atmospheric Projectile program generated miniaturized components and improved propulsion technologies; and the Clementine program is demonstrating dual-use military anal civilian technology. The Naval Center for Space Technology located at the Naval Research Laboratory has developed, fabricated, launched, and operated over 80 small spacecraft since the early 1960s, including the Clementine spacecraft for BMDO. This facility is one of the few government facilities capable of spacecraft development, fabrication, and operation at one location.
Appendix D However, with the end of the Cold War, space technology budgets significantly decreased, and now DoD efforts are being sharply curtailed. Many valuable and important advances in technology for small spacecraft were achieved in past and ongoing programs and are now available for use by NASA and industry. In the future, however, NASA will no longer be able to look to the same degree to DoD as an alternative technology base. The fact that programs are being curtailed emphasizes the need for NASA to step up its activity in research and development related to small spacecraft. 127