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Solar and Space Physics: A Science for a Technological Society
REPORT OF THE PANEL ON SOLAR AND HELIOSPHERIC PHYSICS
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support of space-plasma and solar research, preferably through budget line items for laboratory facilities,
would be beneficial.
10.5.5.7 Interagency Planning for a Future L5 Mission
SHP Imperative: The SHP panel assigns high priority to the development by NASA, NOAA, and DOD
of plans for a mission at the L5 Lagrangian point to conduct helioseismology studies and develop advanced
capabilities to forecast space weather.
Justification: From L5, it is possible to forecast the arrival of Earth-directed CMEs with high precision,
to observe emerging or developed active regions and corotating interaction regions about 4 days earlier
than from Earth, and to measure photospheric magnetic fields over about 60° additional longitude, improving magnetic-field models of regions rotating toward Earth. 45 In addition, stereohelioseismology studies
combining L1 and near-Earth observations have the potential to enable even longer solar-activity forecasts
(§10.3.1 and §10.5.2.5).
The SHP panel encourages NASA, NOAA, and DOD to study means of achieving an L5 orbit for
minimal cost and to define the spacecraft, instrument, and mission requirements needed to optimize the
scientific and operational opportunities from a future L5 mission.
10.6 CONNECTIONS TO OTHER DISCIPLINES
The SHP panel has interests that are connected to those of the Panel on Atmosphere-IonosphereMagnetosphere Interactions (AIMI) and the Panel on Solar Wind-Magnetosphere Interactions (SWMI).
Solar photon radiation and energetic particle outputs are primary energy inputs into and thus drivers of
dynamic processes in Earth’s atmosphere, ionosphere, and magnetosphere and those of other planets. The
Sun varies on timescales of minutes (flares, CMEs, and SEPs), days (27-day solar rotation), years (11-year
solar-activity cycle), and even longer. There are corresponding responses throughout the heliosphere,
including at Earth and other planets. Successful space weather modeling and forecasting of magnetospheric
and ionospheric events include continuous tracing through interplanetary space and monitoring of conditions upstream of Earth. Consequently, most SHP panel initiatives also support AIMI and SWMI goals.
Robust observational and modeling programs of solar outputs and interactive collaborations among the
SHP, AIMI, and SWMI communities are critically important for current and future heliophysics research
and space weather operations.
10.6.1 Earth Science and Climate Change
Solar-irradiance variations in the near-ultraviolet, visible, and near-infrared have direct forcing on
Earth’s climate change because of energy deposition in the lower atmosphere and at the surface and
oceans. The solar-energy input and other indirect forcings, such as top-down coupling of solar ultraviolet
heating and photochemistry in the stratosphere, and the possible influence of galactic cosmic rays, affect
both global climate changes and regional changes that are due to subtle changes in the atmosphere, ocean
circulation patterns, and cloud cover. Solar-irradiance observations and reconstruction and modeling of
long-term variations, such as improved solar-dynamo models, are important support for the Earth science
45 A. Vourlidas et al., Mission to the Sun-Earth L5 Lagrangian Point: An Optimal Platform for Heliophysics and Space Weather
Research, white paper submitted to the Decadal Strategy for Solar and Space Physics (Heliophysics), Paper 273; N. Gopalswamy
et al., Earth-Affecting Solar Causes Observatory (EASCO): A New View from Sun-Earth L5, white paper submitted to the Decadal
Strategy for Solar and Space Physics (Heliophysics), Paper 99.
Solar and Space Physics: A Science for a Technological Society
REPORT OF THE PANEL ON SOLAR AND HELIOSPHERIC PHYSICS
323
support of space-plasma and solar research, preferably through budget line items for laboratory facilities,
would be beneficial.
10.5.5.7 Interagency Planning for a Future L5 Mission
SHP Imperative: The SHP panel assigns high priority to the development by NASA, NOAA, and DOD
of plans for a mission at the L5 Lagrangian point to conduct helioseismology studies and develop advanced
capabilities to forecast space weather.
Justification: From L5, it is possible to forecast the arrival of Earth-directed CMEs with high precision,
to observe emerging or developed active regions and corotating interaction regions about 4 days earlier
than from Earth, and to measure photospheric magnetic fields over about 60° additional longitude, improving magnetic-field models of regions rotating toward Earth. 45 In addition, stereohelioseismology studies
combining L1 and near-Earth observations have the potential to enable even longer solar-activity forecasts
(§10.3.1 and §10.5.2.5).
The SHP panel encourages NASA, NOAA, and DOD to study means of achieving an L5 orbit for
minimal cost and to define the spacecraft, instrument, and mission requirements needed to optimize the
scientific and operational opportunities from a future L5 mission.
10.6 CONNECTIONS TO OTHER DISCIPLINES
The SHP panel has interests that are connected to those of the Panel on Atmosphere-IonosphereMagnetosphere Interactions (AIMI) and the Panel on Solar Wind-Magnetosphere Interactions (SWMI).
Solar photon radiation and energetic particle outputs are primary energy inputs into and thus drivers of
dynamic processes in Earth’s atmosphere, ionosphere, and magnetosphere and those of other planets. The
Sun varies on timescales of minutes (flares, CMEs, and SEPs), days (27-day solar rotation), years (11-year
solar-activity cycle), and even longer. There are corresponding responses throughout the heliosphere,
including at Earth and other planets. Successful space weather modeling and forecasting of magnetospheric
and ionospheric events include continuous tracing through interplanetary space and monitoring of conditions upstream of Earth. Consequently, most SHP panel initiatives also support AIMI and SWMI goals.
Robust observational and modeling programs of solar outputs and interactive collaborations among the
SHP, AIMI, and SWMI communities are critically important for current and future heliophysics research
and space weather operations.
10.6.1 Earth Science and Climate Change
Solar-irradiance variations in the near-ultraviolet, visible, and near-infrared have direct forcing on
Earth’s climate change because of energy deposition in the lower atmosphere and at the surface and
oceans. The solar-energy input and other indirect forcings, such as top-down coupling of solar ultraviolet
heating and photochemistry in the stratosphere, and the possible influence of galactic cosmic rays, affect
both global climate changes and regional changes that are due to subtle changes in the atmosphere, ocean
circulation patterns, and cloud cover. Solar-irradiance observations and reconstruction and modeling of
long-term variations, such as improved solar-dynamo models, are important support for the Earth science
45 A. Vourlidas et al., Mission to the Sun-Earth L5 Lagrangian Point: An Optimal Platform for Heliophysics and Space Weather
Research, white paper submitted to the Decadal Strategy for Solar and Space Physics (Heliophysics), Paper 273; N. Gopalswamy
et al., Earth-Affecting Solar Causes Observatory (EASCO): A New View from Sun-Earth L5, white paper submitted to the Decadal
Strategy for Solar and Space Physics (Heliophysics), Paper 99.