Panel: Future of ILWS - Challenges & opportunities for the next ten years

JAXA plan for solar andheliospheric observations

ILWS Tenth Anniversary Symposium
Vienna, February 14, 2013
United Nations International Centre

Saku Tsuneta
National Astronomical Observatory of Japanhttp://www.ilwsonline.org/tenthanniversary/General tendency of solar physics
missions in the coming 20 years• Combination of high resolution and global
imaging missions• From mere imaging to spectroscopy andspectro-polarimetry• More complete and simultaneous
atmospheric coverage without temperaturegap (with wider wavelength coverage)• Toward out-of-ecliptic

Solar physics
in larger science context• From physical understanding to prediction– Space weather in terms of flares and CMEs
– Space climate in terms of magnetic fields and cosmic
rays, TSI, SSI (UV)• More influence and integration to astrophysics
and geo/planetary sciences– Common physics of magnetized plasma• Good example: magnetic reconnection– Sun and origin of life
• Super-flares• Faint young sun paradox

Open issues in solar physics• Internal structure of the Sun: differential rotation,
meridional flow, turbulent diffusion, and tachocline• Global and turbulent dynamo process• 3D magnetic structure from photosphere through corona• Chromospheric and coronal heating• Prediction of solar flares• Acceleration of fast solar wind
• Fundamental plasma processes in all layers of solar
atmosphere– Propagation and dissipation of waves– Properties and roles of magnetic reconnection• Solar activity and climate

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Solar physics from spacein Japan
188kg

ISAS-NASA-UK Yohkoh/SOLAR-A（1991-2001）

Hinotori/ASTRO-A（1981–1982）

Solar flare observationsin X & γ-rays

390kg

Hard X-ray Flares &soft X-ray corona

ISAS-NASA-UK-ESA Hinode/SOLAR-B（2006–）

900kg

Photospheric magnetic fields

Solar physics from space
Open issues in solar physics
inJapanFundamental plasma processes (SOLARC)
188kg

ISAS-NASA-UK Yohkoh/SOLAR-A
Chromospheric and coronal heating(SOLAR-C)（1991-2001）

Acceleration of fast solar wind (SOLAR-C)
Local dynamo process (SOLAR-C/D)
Hinotori/ASTRO-A（1981–1982）
Internalstructure and flow (SOLAR-D)
Solar flareobservations
Globaldynamoprocess (SOLAR-D) 390kg
in X & γ-rays

SOLAR-C
Systems approach tounderstand solar andheliospheric magnetic
activities and to develop
algorithm for activity
prediction

Hard X-ray Flares &soft X-ray corona

ISAS-NASA-UK-ESA Hinode/SOLAR-B（2006–）

900kg

Photospheric magnetic fields

Solar-C concept• Guiding principle is that small scale plasma
processes associated with magnetic emergence,
waves, shocks, and magnetic reconnection dictate
the evolution of the global phenomena of the Sun
and the heliosphere (and vice versa).
• Observations so far made indicate that observationsof small scale structures and processes are within
our reach.
• Hinode clearly showed that the combination of highspatial resolution and spectroscopy (includingspectro-polarimetry) is a powerful tool for obtaining
magnetic and plasma information.
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Solar-C concept (continued)• To establish magnetic connectivity in terms of both
space and time from photosphere all the way tocorona via 3 means:– By direct measurement of the region plasma-beta <1chromosphere– By computational extrapolation of coronal magnetic fields– By very high resolution EUV observations of corona• This is inevitably achieved with larger telescopeswith highest possible throughput for more photons
and higher spatial resolution. High S/N is critical inorder to retrieve information from spectral profiles.

Solar-C mission definition
Mission: to understand solar and heliospheric magnetic activities andto develop algorithm for solar activity prediction by understanding themagnetic coupling of convection zone-photosphere-chromospheretransition region and corona
Science cases:
1. 3D-magnetic structure withneutral sheets
2. Heating of chromosphereand corona
3. Acceleration of fast solar
wind
4. Prediction of solar flares
5. Fundamental plasma
processes such asreconnection, waves,shocks, particle
acceleration andturbulence
6. Global and local dynamo
7. Sun’s influence to EarthclimateKey requirements:
1. High spatial resolution to see more elemental
structure inferred by Hinode
2. High time resolution to freeze rapidly changing
chromospheric phenomena
3. Chromospheric magnetic observations
4. Seamless spectroscopic imaging observations
from photosphere to corona
5. Wide FOV to connect local and global and tocover ARImaging spectroscopy instruments:
X-ray/EUV: ultra-highVisible: 1.5m-classresolution EUV telescopes
telescope to obtain 3Dwith optional photonmagnetic structure fromcountng telescope
photosphere to corona
UV: high-throughput
with x10 more photons,
telescope x10 more
and x3 resolution withsensitive with seamlesshigh cadence
coverage in temperatureHinode observations onsolar north poleminus←B→plus

北極点North pole
80 degree

北緯80度

70 degree

September 2007
Tsuneta+08, Ito+ 10, Shiota+ 12

70度
60度
September
2012
55度

11Hinodemagnetic flux in polar regions
Averageflux(G)North pole

South pole

minus

plus

plus

minus

yearyear• North pole: reversal going on• South pole: stationary12Solar-D out-ofecliptic mission
Telescopes
Sun sensors
HGAStar sensors
Mu-20 advanced
Ion engines
~1.5m

~1.2m
~2.0m

~1.5m

Model instruments (min100kg)
Doppler magnetic imager
X-ray/EUV imager
Total irradiance monitor
In-situ instruments

Technology developmentwith ISAS small satellite#3:
1. Advanced ion-engine
2. Ultra light weight solar paddle
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Solar&helio physics roadmap
2011-2030: From SOLAR-C to SOLAR-D
2010

A-D

=Mission proposal to ISAS/JAXA

Solar-D(ISAS small satellite series #3)
Verification of large ion engine
and other technologies to be used
for future deep space missions
Rev. B: 12 Feb.2013
Rev. A: 11 March 2011

A

Pre-A
MDR
SRR

Out-of-ecliptic mission(Success-guaranteed plan A-satellite)

Engineering mission

Project

WG Activities

B/C D
CDR

MDR
SRR

B/C D

PDR

A

Project

CDR

Pre-A

Launch (Japan FY 2019)

PDR

WG Activities

High resolution spectroscopy(plan B-satellite)

CLASP Sounding rocket

Solar maximum

Solar maximum
PreProject

Solar-C

2030

SDR

HINODE(Solar-B)

2020

SDR

Japan FY

Launch (Japan FY 2018)
Pre-A

A

B/C

D
In Orbit verification

Pre-A: Pre-Phase-A (WG activities)
A: Phase-A (R&D)
B/C: Phase-B/C (PM phase)14
D: Phase-D (FM phase)Summary• Japan has been contributing to better
understanding on the fundamental plasma
processes taking place on the sun with 3 JAXA
solar missions. We continue to do so with theproposed Solar-C mission.
• We recognize the importance of heliophysics
in terms of its societal and environmental
effects on Earth. We desire to contribute toILWS activity with existing and planned JAXAmissions.

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