The full observational assets of ISTP have been operational now for slightly over a year. The strategic locations of the ISTP/GGS spacecraft, WIND, POLAR and GEOTAIL, allow fundamental measurements to be obtained on the flow of energy, mass and momentum from the Sun, through the heliosphere, into the magnetosphere, with eventual dissipation in the Earth’s atmosphere. With SOHO, the many other collaborating spacecraft, ground based observatories and theory element, the ISTP/GGS program has already produced surprising discoveries and demonstrated excellent capabilities for fulfilling its present objectives as well as proposed future objectives.
For the first time transient events have been followed from their birth on the Sun, traced through the interplanetary medium, characterized as they near the Earth, and quantified in terms of their geoeffectiveness in creating magnetic storms and accelerating geospace plasmas. For each step in this process, the ISTP/GGS program has produced important new findings that are leading to an increased understanding of the system as a whole and how individual parts of this closely coupled, highly time dependent system work together. New and greatly improved capabilities of this "great distributed observatory" enable access to plasma regimes never observed before. Theoretical models and computer global simulations using WIND measurements as input are now being compared to GGS observations to validate our understanding of fundamental solar-terrestrial processes.
The scientific achievements of ISTP/GGS have been matched on the ground by significant improvements in data processing, access and validation, networks, public data access, education and outreach. These have made possible the prompt detection, identification, preliminary analysis, and distribution of results about solar-terrestrial events much more quickly than previous programs, resulting in unprecedented scientific productivity and public awareness about the Sun-Earth connected system. The GGS data are open to all scientists and its accessibility and scientific value is evidenced by the five days of special sessions with more than 200 papers presented at the American Geophysical Union meeting last December!
The inevitable increase in solar activity associated with the solar cycle will generate a commensurate response from the geospace environment. We can expect to encounter large solar energetic particle events, great magnetic storms with associated highly variable electric current systems, intense penetrating MeV trapped electron populations, and auroral ionization extending to low latitudes. The increased intensity and frequency of events in geospace will enable the systematic study of previously less frequent physical processes, yielding increased understanding of cause-effect relationships over much larger ranges of parameters, and significant improvements in associated theoretical and modeling efforts. The next few years provide an unprecedented potential for discoveries and a unique opportunity to significantly increase our understanding of Sun-Earth connections, from solar minimum through solar maximum.
Within the NASA Sun-Earth Connection program, ISTP/GGS assets must be a fundamental element with their already global system approach using state-of-the art scientific, measurement, operational and ground-based tools. These are required to carry out a world class research program, to support the National Space Weather Program with pioneering science, and to provide unparalleled access to the solar-terrestrial data to the scientific community, industry and the public during this high activity period.
Based on its scientific merit, national importance and critical support of major agency goals, we propose a new program, GGS/SOLARMAX, that will result in significant advances in our understanding of the Sun Earth connected system and in the predictive capabilities of the large-scale geospace system response during all phases of the solar cycle.
The GGS/SOLARMAX program emphasizes three fundamental themes for FY1998-FY2001:
- Science theme: Quantitatively analyze the fundamental global characteristics of the Solar-Terrestrial system before and during solar maximum, to complement the seminal achievements by ISTP near solar minimum.
- Technology theme: Develop an information base for assessment of the impact to high technology systems of energetic and transient phenomena in the Sun-Earth system, that are known to increase dramatically during solar maximum.
- Public service theme: Exploit the space and ground-based ISTP assets to provide exceptional service to the scientific, educational and industrial communities during the maximum phase of the solar cycle
The fundamental goal of understanding a variable magnetic star and a magnetized planetary atmosphere accessible to in-situ and detailed remote observations has direct implications for the general understanding of astrophysical objects which will remain forever inaccessible. The long term variations of our own atmosphere are coupled via poorly understood mechanisms to physical processes taking place in the solar-terrestrial system. The increasing and critical dependence of our civilization on advanced space technologies ultimately requires a complete understanding of the geospace environment to fully assess its impact on these critical systems, particularly from extremes of activity during solar maximum. Human access to space is limited by the vulnerability of crews and machines to the space environment. Because these systems are becoming part of common activities in everyday life, industry and the public are becoming increasingly aware of the nature and impact of solar terrestrial events.
To accomplish the science proposed for SOLARMAX, we must continue the paradigm of the ISTP program of acquiring simultaneous data from critical locations in the Sun-Earth connected system. We will use the elements of the ISTP program that represent a direct investment of
nearly $2.4B by the United States and international collaborators for the implementation of this unique, distributed observatory. We have laid out a cost effective program that is highly leveraged because of the use, at a small relative cost, of the many facilities already in place. From a programmatic standpoint, this new program is especially attractive because it will have no development costs, no launch costs, no start-up costs, no delays and no cost-overruns.
Reengineering of the mission operations based on the experience gained during the development and full operation (since February, 1996) of ISTP/GGS will make possible a very efficient streamlining of spacecraft and science operations, resulting in significantly reduced resource requirements. In this new environment, research is funded primarily through an open and competitive science program, and preserves the PI appointments from ISTP/GGS for science operations and data validation. The synergistic integration of networks and advanced scientific visualization, planning, analysis and operations software into the system will enable prompt and efficient scientific evaluation of the data by a very large cross-section of the scientific community. All of these changes will result in the realization of a maximum science-per-dollar ratio.
The GGS/SOLARMAX program is fully responsive to the requested cost guidelines. Our minimum proposed science program is 53% of current funding and maximizes participation of the Sun Earth Connection science community through a Competitive Science Program. The desired funding level maintains the operational baseline of the minimum program and further increases support for competitive science research. New Obligation Authority required for the minimum viable program is: FY1998, POP96-1; FY1999, $3.7M; FY2000, $11.2M; FY2001, $11.2M. The desired funding level maintains the operational baseline of the minimum program and further increases support for competitive science research by $5M each year.