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Solar and Space Physics: A Science for a Technological Society
NSF PROGRAM IMPLEMENTATION
119
An All-Atmosphere Lidar Observatory
The most significant discoveries in the AIM discipline over the past decade involve increased appreciation of the influence of neutral atmospheric waves and instabilities on ionospheric structure and dynamics.
An impediment to further research is the lack of direct, ground-based observations of the dynamics and
thermodynamics of the mesosphere and, crucially, the thermosphere. Recent technical developments in
the areas of high-power Rayleigh lidar and new resonance lidars now offer the possibility of wind and
temperature measurements from the ground well into the thermosphere for the first time. A lidar observatory capable of observing gravity waves and tides and associated phenomenology in the mesosphere and
lower thermosphere would accelerate discovery across the AIM discipline.
A Heterogeneous Ionospheric Facility Network
Processes central to AIM science are multiscale in nature, with global features that extend from the
equator to the poles together with local features such as embedded small-scale irregularities that intermittently affect communications. Examples include traveling ionospheric disturbances, regions of stormenhanced density, and the ionospheric response to sudden stratospheric warming events. Capturing these
phenomena will require the deployment of an autonomous network of heterogeneous instruments, using
optical and radio remote sensing techniques to measure neutral winds and temperatures, plasma densities,
and plasma irregularities. Such a network would become a valuable facility in its own right, comparable to
an EarthScope USArray 5 for heliophysics, and would also be the ground-based counterpart to space-based
investigations, complementing everything from CubeSat projects to NASA strategic missions.
A Southern-Hemisphere Incoherent Scatter Radar
The AMISR phased-array incoherent scatter radar has proven to be a most incisive instrument for
measuring the state properties of the ionosphere with panoramic coverage and high precision. Unknown,
however, is the degree of inter-hemispheric conjugacy that can be assumed. The next logical step is to
deploy an AMISR face in the Southern Hemisphere, expanding the latitudinal coverage of the heterogeneous
network further. A deployment in the Antarctic region in particular would allow for the first ground-based
assessment of conjugacy of geomagnetic storms.
Next-Generation Ground-Based Instrumentation
There is a need to support continuing instrumentation and technology development for ground-based
solar physics in both the national facilities and the universities. Support for advanced instrumentation and
seeing-compensation techniques for the ATST and other solar telescopes is necessary to keep groundbased solar physics at the cutting edge. At the same time it is necessary to ensure that adequate support
is available to nurture young scientists and engineers in the field of solar instrumentation. That implies a
need for adequate funding and good career opportunities, including the opportunity to work on exciting
new instrumentation projects.
5 See EarthScope, “USArray Instrumentation Network,” available at http://www.earthscope.org/observatories/usarray.
Solar and Space Physics: A Science for a Technological Society
NSF PROGRAM IMPLEMENTATION
119
An All-Atmosphere Lidar Observatory
The most significant discoveries in the AIM discipline over the past decade involve increased appreciation of the influence of neutral atmospheric waves and instabilities on ionospheric structure and dynamics.
An impediment to further research is the lack of direct, ground-based observations of the dynamics and
thermodynamics of the mesosphere and, crucially, the thermosphere. Recent technical developments in
the areas of high-power Rayleigh lidar and new resonance lidars now offer the possibility of wind and
temperature measurements from the ground well into the thermosphere for the first time. A lidar observatory capable of observing gravity waves and tides and associated phenomenology in the mesosphere and
lower thermosphere would accelerate discovery across the AIM discipline.
A Heterogeneous Ionospheric Facility Network
Processes central to AIM science are multiscale in nature, with global features that extend from the
equator to the poles together with local features such as embedded small-scale irregularities that intermittently affect communications. Examples include traveling ionospheric disturbances, regions of stormenhanced density, and the ionospheric response to sudden stratospheric warming events. Capturing these
phenomena will require the deployment of an autonomous network of heterogeneous instruments, using
optical and radio remote sensing techniques to measure neutral winds and temperatures, plasma densities,
and plasma irregularities. Such a network would become a valuable facility in its own right, comparable to
an EarthScope USArray 5 for heliophysics, and would also be the ground-based counterpart to space-based
investigations, complementing everything from CubeSat projects to NASA strategic missions.
A Southern-Hemisphere Incoherent Scatter Radar
The AMISR phased-array incoherent scatter radar has proven to be a most incisive instrument for
measuring the state properties of the ionosphere with panoramic coverage and high precision. Unknown,
however, is the degree of inter-hemispheric conjugacy that can be assumed. The next logical step is to
deploy an AMISR face in the Southern Hemisphere, expanding the latitudinal coverage of the heterogeneous
network further. A deployment in the Antarctic region in particular would allow for the first ground-based
assessment of conjugacy of geomagnetic storms.
Next-Generation Ground-Based Instrumentation
There is a need to support continuing instrumentation and technology development for ground-based
solar physics in both the national facilities and the universities. Support for advanced instrumentation and
seeing-compensation techniques for the ATST and other solar telescopes is necessary to keep groundbased solar physics at the cutting edge. At the same time it is necessary to ensure that adequate support
is available to nurture young scientists and engineers in the field of solar instrumentation. That implies a
need for adequate funding and good career opportunities, including the opportunity to work on exciting
new instrumentation projects.
5 See EarthScope, “USArray Instrumentation Network,” available at http://www.earthscope.org/observatories/usarray.