Article

The DynaMICCS perspective. A mission for a complete and continuous view of the Sun dedicated to magnetism, space weather and space climate

Experimental Astronomy (Impact Factor: 2.66). 03/2009; 23(3):1017-1055. DOI: 10.1007/s10686-008-9111-z

ABSTRACT The DynaMICCS mission is designed to probe and understand the dynamics
of crucial regions of the Sun that determine solar variability,
including the previously unexplored inner core, the radiative/convective
zone interface layers, the photosphere/chromosphere layers and the low
corona. The mission delivers data and knowledge that no other known
mission provides for understanding space weather and space climate and
for advancing stellar physics (internal dynamics) and fundamental
physics (neutrino properties, atomic physics, gravitational moments...).
The science objectives are achieved using Doppler and magnetic
measurements of the solar surface, helioseismic and coronographic
measurements, solar irradiance at different wavelengths and in-situ
measurements of plasma/energetic particles/magnetic fields. The
DynaMICCS payload uses an original concept studied by Thalès
Alenia Space in the framework of the CNES call for formation flying
missions: an external occultation of the solar light is obtained by
putting an occulter spacecraft 150 m (or more) in front of a second
spacecraft. The occulter spacecraft, a LEO platform of the mini sat
class, e.g. PROTEUS, type carries the helioseismic and irradiance
instruments and the formation flying technologies. The latter spacecraft
of the same type carries a visible and infrared coronagraph for a unique
observation of the solar corona and instrumentation for the study of the
solar wind and imagers. This mission must guarantee long (one 11-year
solar cycle) and continuous observations (duty cycle > 94%) of
signals that can be very weak (the gravity mode detection supposes the
measurement of velocity smaller than 1 mm/s). This assumes no
interruption in observation and very stable thermal conditions. The
preferred orbit therefore is the L1 orbit, which fits these requirements
very well and is also an attractive environment for the spacecraft due
to its low radiation and low perturbation (solar pressure) environment.
This mission is secured by instrumental R and D activities during the
present and coming years. Some prototypes of different instruments are
already built (GOLFNG, SDM) and the performances will be checked before
launch on the ground or in space through planned missions of CNES and
PROBA ESA missions (PICARD, LYRA, maybe ASPIICS).

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