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Solar and Space Physics: A Science for a Technological Society
238
SOLAR AND SPACE PHYSICS: A SCIENCE FOR A TECHNOLOGICAL SOCIETY
can be expected from analysis of data from the NASA and other agency spacecraft already in orbit.
Together with new missions as they come on line, these assets constitute the space-based elements of
the Heliophysics Systems Observatory, providing multipoint simultaneous measurements essential to
advancing the SWMI science goals.
Ground-based observations. Ground-based measurements are commonly combined with spacecraft
measurements to understand magnetospheric processes. In some cases, it has proven beneficial to
install additional ground-based instruments in support of a specific spacecraft mission. This is exemplified most recently by the THEMIS mission, which included a 20-camera all-sky imaging array and
21 magnetometers installed in the northern United States and Canada.
Theory and modeling. The complexity of the solar wind-magnetosphere-ionosphere system, combined
with its vastness, guarantees that the system will be greatly undersampled regardless of the number of
spacecraft placed in orbit. While global remote-sensing capabilities help, they introduce complexities
of their own, such as the fact that they often view an optically thin medium. Thus, to fully exploit the
variety of available measurements and to put them into the proper interpretive physical perspective,
theory and modeling are crucial. The enormous improvements in numerical modeling capabilities over
the past decades have led to major progress in physical understanding of the system; with appropriate
investment, these improvements will continue through the next decade.
Laboratory experiments. With spacecraft measurements, scientists observe whatever behavior nature
provides. There is no way to repeat an experiment or to isolate a single parameter for investigation
in the classical model of physical experimentation. This can be remedied by supplementing satellite
observations with appropriately designed laboratory experiments, which can reveal significant aspects
of the physical processes operating in space. Such experiments also provide a touchstone for testing
numerical models.
Grants programs. Finally, the heartbeat of space physics is the set of grants programs administered by
NASA and NSF, which underlie essentially all the progress that emerges from the various data sources.
These relatively small, investigator-led studies enable researchers to exploit the data from missions and
connect them to relevant theoretical frameworks.
The SWMI panel strongly supports the survey committee’s conclusion that the key science goals identified in this decadal survey can be most effectively accomplished with a well-balanced program that uses
the full spectrum of implementation options. This same approach is needed for the achievement of the
SWMI panel goals discussed in this chapter. The optimum balance is of course challenging to identify, but
in the course of this decadal survey, the SWMI panel identified a number of areas where new attention or
enhanced resources could significantly increase the ability to deliver the important science goals outlined
above. Seeking and protecting the appropriate balance of these capabilities is the overarching theme of
the imperatives the SWMI panel believes are required to successfully address the critical SWMI science
goals outlined above. These imperatives fall into three categories:
• Missions,
• DRIVE-related initiatives (see Chapter 4 for DRIVE description and discussion), and
• Space weather.
The remainder of this section addresses the SWMI panel’s imperatives in each of these categories.
Solar and Space Physics: A Science for a Technological Society
238
SOLAR AND SPACE PHYSICS: A SCIENCE FOR A TECHNOLOGICAL SOCIETY
can be expected from analysis of data from the NASA and other agency spacecraft already in orbit.
Together with new missions as they come on line, these assets constitute the space-based elements of
the Heliophysics Systems Observatory, providing multipoint simultaneous measurements essential to
advancing the SWMI science goals.
Ground-based observations. Ground-based measurements are commonly combined with spacecraft
measurements to understand magnetospheric processes. In some cases, it has proven beneficial to
install additional ground-based instruments in support of a specific spacecraft mission. This is exemplified most recently by the THEMIS mission, which included a 20-camera all-sky imaging array and
21 magnetometers installed in the northern United States and Canada.
Theory and modeling. The complexity of the solar wind-magnetosphere-ionosphere system, combined
with its vastness, guarantees that the system will be greatly undersampled regardless of the number of
spacecraft placed in orbit. While global remote-sensing capabilities help, they introduce complexities
of their own, such as the fact that they often view an optically thin medium. Thus, to fully exploit the
variety of available measurements and to put them into the proper interpretive physical perspective,
theory and modeling are crucial. The enormous improvements in numerical modeling capabilities over
the past decades have led to major progress in physical understanding of the system; with appropriate
investment, these improvements will continue through the next decade.
Laboratory experiments. With spacecraft measurements, scientists observe whatever behavior nature
provides. There is no way to repeat an experiment or to isolate a single parameter for investigation
in the classical model of physical experimentation. This can be remedied by supplementing satellite
observations with appropriately designed laboratory experiments, which can reveal significant aspects
of the physical processes operating in space. Such experiments also provide a touchstone for testing
numerical models.
Grants programs. Finally, the heartbeat of space physics is the set of grants programs administered by
NASA and NSF, which underlie essentially all the progress that emerges from the various data sources.
These relatively small, investigator-led studies enable researchers to exploit the data from missions and
connect them to relevant theoretical frameworks.
The SWMI panel strongly supports the survey committee’s conclusion that the key science goals identified in this decadal survey can be most effectively accomplished with a well-balanced program that uses
the full spectrum of implementation options. This same approach is needed for the achievement of the
SWMI panel goals discussed in this chapter. The optimum balance is of course challenging to identify, but
in the course of this decadal survey, the SWMI panel identified a number of areas where new attention or
enhanced resources could significantly increase the ability to deliver the important science goals outlined
above. Seeking and protecting the appropriate balance of these capabilities is the overarching theme of
the imperatives the SWMI panel believes are required to successfully address the critical SWMI science
goals outlined above. These imperatives fall into three categories:
• Missions,
• DRIVE-related initiatives (see Chapter 4 for DRIVE description and discussion), and
• Space weather.
The remainder of this section addresses the SWMI panel’s imperatives in each of these categories.