METIS, the Multi Element Telescope for Imaging and Spectroscopy for the Solar Orbiter mission

In 1999 the European solar scientific community proposed to ESA the Solar Orbiter (SO), a mission to explore the circumsolar region, to perform quasi helio-synchronous observations, and to obtain the first out-of-ecliptic imaging and spectroscopy of the solar poles and of the equatorial corona. Presently, SO is one of the three missions under study within the ESA Cosmic Vision 2015-2025 program, and a key ESA-NASA missions within the International Living with a Star Program. SO, to be launched on January 2017, is expected to provide major advances steps forward in understanding the Sun-heliosphere connection. METIS, the Multi Element Telescope for Imaging and Spectroscopy, is one of the instruments selected in 2009 by the European Space Agency to be part of the payload of the SO mission. The instrument design has been conceived by an international team with the intent to perform both multiband imaging and UV spectroscopy of the solar corona. METIS, owing to its multi wavelength capability, can effectively address some of the major open issues in understanding the corona and the solar wind can be effectively addressed, exploiting the unique opportunities offered by the SO mission profile. METIS observations are crucial for answering some fundamental solar physics questions concerning the origins of the fast and slow wind, the sources of solar energetic particles, and the eruption and early evolution of coronal mass ejections. METIS adopts an innovative optical design [1] which perfectly adapts to the critical environment