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Solar and Space Physics: A Science for a Technological Society
294
SOLAR AND SPACE PHYSICS: A SCIENCE FOR A TECHNOLOGICAL SOCIETY
The SHP panel gives its unqualified endorsement to the SPP mission as long as it satisfies cost and schedule
guidelines. 8
10.4.6.2 Science Goals for Solar Orbiter
In October 2011, ESA’s Science Programme Committee unanimously selected Solar Orbiter as the
Cosmic Vision M1 mission, and it was scheduled for launch in 2017. Solar Orbiter will investigate links
between the solar surface, corona, and inner heliosphere from as close as 62 R S by using a comprehensive payload that combines remote-sensing and in situ measurements. NASA’s LWS program will provide
the launch vehicle and critical science instruments and investigations. Two instruments that had been
descoped by NASA were restored with ESA funding, and so the complete payload will fly as originally
planned. When close to the Sun, Solar Orbiter will observe emissions, solar wind, and energetic particles
from a single area for much longer than is possible from 1 AU and will provide improved insight into
the evolution of sunspots, active regions, coronal holes, and other solar features and phenomena. Solar
Orbiter’s high spatial and time-resolution observations close to the Sun and its long observations during
near corotation with the Sun will probe key questions for understanding the formation of the heliosphere
and the generation of space weather events:
• How and where do the solar wind plasma and magnetic field originate in the corona (SHP action 2d)?
• How do solar transients drive heliospheric variability (SHP actions 2d and 3a)?
• How do solar eruptions produce energetic-particle radiation that fills the heliosphere (SHP actions
3a-c)?
• How does the solar dynamo work and drive connections between the Sun and heliosphere (SHP
action 1b)?
A unique aspect of the mission occurs when the spacecraft’s orbital plane is increased to about 35°
solar latitude, permitting definitive measurements of polar magnetic fields and high-quality observations of
solar oscillations in the polar region and thereby supplying a missing link in observations of solar globalcirculation patterns (SHP action 1a). Solar Orbiter and SPP observations will overlap in time, permitting
many opportunities for coordinated inner-heliosphere measurements that will greatly increase the science
return from both missions. Solar Orbiter out-of-ecliptic measurements contemporaneous with near-ecliptic
measurements will provide unprecedented insights into the evolving three-dimensional inner heliosphere
and outer corona. For example, the remotely observed polar magnetic field combined with in situ observations by SPP will provide tests of the magnetic flux transport model (SHP action 1a).
Data return using U.S. tracking assets to provide enhanced temporal coverage for helioseismology and
other uses would provide improved measurements of the solar interior, including such aspects as variations
near the bottom of the convection zone and meridional flows, which are important for understanding the
generation of solar activity. The scientific return of Solar Orbiter would also be greatly enhanced by providing postlaunch funding opportunities for investigations that would not directly support U.S. instruments
but would have important involvement of U.S. investigators.
The SHP panel strongly endorses NASA’s highly leveraged participation in this mission.
8 Solar Probe Plus successfully completed its mission design review in November 2011 and proceeded into preliminary design. As
this report went to press, it was scheduled for launch in July 2018.
Solar and Space Physics: A Science for a Technological Society
294
SOLAR AND SPACE PHYSICS: A SCIENCE FOR A TECHNOLOGICAL SOCIETY
The SHP panel gives its unqualified endorsement to the SPP mission as long as it satisfies cost and schedule
guidelines. 8
10.4.6.2 Science Goals for Solar Orbiter
In October 2011, ESA’s Science Programme Committee unanimously selected Solar Orbiter as the
Cosmic Vision M1 mission, and it was scheduled for launch in 2017. Solar Orbiter will investigate links
between the solar surface, corona, and inner heliosphere from as close as 62 R S by using a comprehensive payload that combines remote-sensing and in situ measurements. NASA’s LWS program will provide
the launch vehicle and critical science instruments and investigations. Two instruments that had been
descoped by NASA were restored with ESA funding, and so the complete payload will fly as originally
planned. When close to the Sun, Solar Orbiter will observe emissions, solar wind, and energetic particles
from a single area for much longer than is possible from 1 AU and will provide improved insight into
the evolution of sunspots, active regions, coronal holes, and other solar features and phenomena. Solar
Orbiter’s high spatial and time-resolution observations close to the Sun and its long observations during
near corotation with the Sun will probe key questions for understanding the formation of the heliosphere
and the generation of space weather events:
• How and where do the solar wind plasma and magnetic field originate in the corona (SHP action 2d)?
• How do solar transients drive heliospheric variability (SHP actions 2d and 3a)?
• How do solar eruptions produce energetic-particle radiation that fills the heliosphere (SHP actions
3a-c)?
• How does the solar dynamo work and drive connections between the Sun and heliosphere (SHP
action 1b)?
A unique aspect of the mission occurs when the spacecraft’s orbital plane is increased to about 35°
solar latitude, permitting definitive measurements of polar magnetic fields and high-quality observations of
solar oscillations in the polar region and thereby supplying a missing link in observations of solar globalcirculation patterns (SHP action 1a). Solar Orbiter and SPP observations will overlap in time, permitting
many opportunities for coordinated inner-heliosphere measurements that will greatly increase the science
return from both missions. Solar Orbiter out-of-ecliptic measurements contemporaneous with near-ecliptic
measurements will provide unprecedented insights into the evolving three-dimensional inner heliosphere
and outer corona. For example, the remotely observed polar magnetic field combined with in situ observations by SPP will provide tests of the magnetic flux transport model (SHP action 1a).
Data return using U.S. tracking assets to provide enhanced temporal coverage for helioseismology and
other uses would provide improved measurements of the solar interior, including such aspects as variations
near the bottom of the convection zone and meridional flows, which are important for understanding the
generation of solar activity. The scientific return of Solar Orbiter would also be greatly enhanced by providing postlaunch funding opportunities for investigations that would not directly support U.S. instruments
but would have important involvement of U.S. investigators.
The SHP panel strongly endorses NASA’s highly leveraged participation in this mission.
8 Solar Probe Plus successfully completed its mission design review in November 2011 and proceeded into preliminary design. As
this report went to press, it was scheduled for launch in July 2018.