The Extreme Ultraviolet Imager (EUI) is a suite for optical imaging
designed for the Solar Orbiter
spacecraft. Solar Orbiter will be lauched in 2017 and its nominal mission
lasts until 2024 (with the possiblity of an extended mission until 2026). This means that the imagers will be able to monitor the
Sun activity in a period which covers the transition from the maximum
to the minimum of the 11 year solar cycle. Along the orbit, the spacecraft
will approach the Sun as close at 0.30 AU at perihelion, while the maximum
aphelion is located at about 0.95 AU. Further more, about 3 years after the
launch, the spacecraft will begin an out-of ecliptic phase, with
an inclination which increases toward the maximum value of about 30º
with respect to the equatorial plane.
Main EUI features (the FOV and the resolution in distance are computed assuming a perihelion and aphelion of 0.30 and 0.95 AU).
continuosly monitors the full Sun in two bandpasses (a
The two HRIs, on the contrary, have a limited field of
view in favour of a higher cadence and an increased spatial
resolution. They will be operating only during
the closest approaches to the Sun and in limited, well-defined observing
periods. Their bandpasses have been selected in
order to monitor a region at three different temperatures (typical
emission lines of the chormosphere, transition region and low corona
are chosen), which allows to establish the spatial and temporal
connection of the observed structures as
they develop in the different layers of the atmosphere.