Since the 1980s, the collaborative efforts by NASA, the European Space
Agency (ESA), and the Institute of Space and Astronuatical Science (ISAS)
of Japan have led to the conception of the International Solar-Terrestrial
Physics Science Initiative consisting of a set of solar-terrestrial
missions to be carred out during the 1990s and into the next century.
This program combines resources and scientific communities on an
international scale using a complement of several missions, along with
complementary ground facilities and theoretical efforts, to obtain
coordinated, simultaneous investigations of the Sun-Earth space
environment over an extended period of time.
Primary Science Objectives
The primary science objectives of the ISTP Science Initiative are as
- Determining structure and dynamics in the solar interior and their
in driving solar activity.
- Identifying processes responsible for heating the solar corona and its
acceleration outward as the solar wind.
- Determining the flow of mass, momentum and energy through geospace.
- Gaining a better understanding of the turbulent plasma phenomena that
mediate the flow of energy through geospace.
- Implementing a systematic approach to the development of the first
global solar-terrestrial model, which will lead to a better understanding
of the chain of cause-effect relationships that begins with solar activity
and ends with the deposition of energy in the upper atmosphere.
The ISTP Science Initiative uses simultaneous and closely coordinated
measurements from GEOTAIL, WIND, POLAR, SOHO and
Cluster. These measurements of the key regions of geospace will be
supplemented by data from Equatorial missions and ground-based
investigations. The Equatorial missions include: the Geosynchronous
Operational Environmental Spacecraft (
GOES) Program of the National Oceanic and Atmospheric Administration
(NOAA) and the Los Alamos National Laboratory (
LANL) spacecraft from the Department of Energy (DOE). The
ground-based investigations include:
Additional data from other satellites such as NASA's IMP-8 satellite are used to
supplement the data from these missions.
These missions and investigations will provide a measurement network to
determine the local state of several key magnetospheric regions. However,
because the magnetosphere is a vast interactive system, a comprehensive
understanding can be acheived only if local measurements can be related to
large-scale structure observations.
The integration of theory and modeling with satellite and ground-based
observations completes the ISTP Science Initiative.
Spacecraft and Instruments Summary
Ground Based Investigations Summary
ISTP Principal Investigator List