Solar Orbiter EUI

Solar Orbiter EUI (since 2006)

On the 4th of October 2011, Solar Orbiter has been selected by the ESA's Science Programme Committee (SPC) as the M1 mission of the Cosmic Vision programme, to be launched in 2017.
Solar Orbiter will provide the next major step forward in the exploration of the Sun and the heliosphere to investigate many of the fundamental problems remaining in solar and heliospheric science. It includes both a near-Sun and a high solar latitude phase. The near-Sun phase of the mission enables the spacecraft to approach the Sun as close as 0.28 Astronomical Unit (AU) during part of its orbit and thereby permitting observations from a quasi heliosynchronous vantage point. The satellite will co-rotate with the Sun, as at these distances the angular speed of a spacecraft near its perihelion approximately matches the rotation rate of the Sun. This characteristic enables the instruments to track a given point on the Sun surface for several days. According to this spacecraft configuration, several surfaces, components and subsystems shall be directly exposed to a solar flux profile ranging from 0.5 SC up to 13 SC.
The EUI instrument suite is composed of two high-resolution imagers (HRI), one operating at Lyman-α and one at 174Å, respectively named “HRILy-α” and “HRIEUV”, and one dual band full-sun imager (FSI) working alternatively at the 174 and 304 Å EUV passbands. The HRI and FSI images are produced by a two-mirror and a one-mirror telescope respectively, working in near normal incidence. The EUV reflectivity of the optical surfaces obtained with specific EUV multilayered coating provides the spectral selection, complemented by filters rejecting the visible and IR radiation. The UV photons reach the detectors (back-thinned APS of 10μm 2k x 2k for the HRI channels and 10μm 3k x 3k for the FSI channel) where they are converted into electrical signal in a front-end electronic (FEE), before being compressed and stored in the CEB (common electronic box).
The CSL is the PI Institute of the EUI Consortium including members from Belgium, France, Germany, Switzerland and United Kingdom.


See  Solar Orbiter EUI (Optical Design & Metrology)

See also ESA Solar Orbiter Site


solar orbieter euisolar orbiter filtresolar orbiter instrument

Solar Orbiter EUI heat

rejection baffle prototype.

Solar Orbiter EUI entrance filter

prototype under test at CSL

Solar Orbiter EUI instrument

CAD view


Contact(s) : Jean-Philippe Hallain