The Comet Interceptor mission was selected by ESA in June 2019 as ESA's new fast-class mission in its Cosmic Vision Programme. Comprising three spacecraft, it will be the first to visit a Long Period Comet (LPC) or even an interstellar object that is only just starting its journey into the inner Solar System. The RMA, under CSL responsibility, is a mechanism rotating a mirror which ensures that the comet is kept within the FoV of the CoCa instrument during the closest part of the approach. The RMA is composed of the Scanning Mirror Assembly (SMA), including a protection baffle, and the associated electronics (SME). The technical role of CSL is to design, develop, build and verify the SMA to be finally delivered to ESA as part of the RMA. This paper introduces the current activities on the RMA development with a deeper insight on the design steps and the preliminary results of the performed breadboard tests (mechanism actuation and coating impact tests). Additional presentation content can be accessed on the supplemental content page.
The Extreme Ultraviolet Imager (EUI) instrument for the Solar Orbiter mission will image the solar corona in the extreme ultraviolet (17.1 nm and 30.4 nm) and in the vacuum ultraviolet (121.6 nm) spectral ranges. The development of the EUI instrument has been successfully completed with the optical alignment of its three channels’ telescope, the thermal and mechanical environmental verification, the electrical and software validations, and an end-toend on-ground calibration of the two-units’ flight instrument at the operating wavelengths. The instrument has been delivered and installed on the Solar Orbiter spacecraft, which is now undergoing all preparatory activities before launch.
SWAP (SWAP (Sun Watcher using Active Pixel System detector and Image Processing) is an instrument that has been selected to fly on the PROBA- 2 technology demonstration platform, a program of the European Space Agency (ESA) to be launched in 2006. SWAP is based on an off-axis degraded Ritchey Chretien telescope that will image the EUV solar corona at 19.5 nm on a specifically fabricated extreme ultraviolet (EUV) sensitivity enhanced CMOS APS detector. The optical design and the optical coatings are derived from the Extreme Ultraviolet Imaging Telescope (EIT) operating on-board SOHO since 1995 [1]. It has been adapted for a single wavelength telescope with off-axis optics. It allows to use smaller optics and filters, with simple internal baffles avoiding external protruding parts. The superpolished optics will receive a multilayer coating that provides spectral selection centred on 19.5 nm and EUV reflectivity in normal incidence. This compact design is specifically adapted for accommodation on PROBA-2, where mass and envelope requirements are very stringent The SWAP PROBA-2 program will be an opportunity to demonstrate this new optical concept, while it will also validate space remote sensing with APS detectors, as well as on-board image processing capabilities. On the science outcomes, SWAP will provide solar corona images in the Fe XII line on a baselined 2-min cadence. Observations with this specific wavelength allow detecting phenomena, such as solar flares or ‘EIT-waves’, associated with the early phase of coronal mass ejections. The SWAP data will complement the observations provided by SOHO-EIT, and STEREOSECCHI.
is an instrument that has been selected to fly on the PROBA- 2 technology demonstration platform, a program of the European Space Agency (ESA) to be launched in 2006. SWAP is based on an off-axis degraded Ritchey Chretien telescope that will image the EUV solar corona at 19.5 nm on a specifically fabricated extreme ultraviolet (EUV) sensitivity enhanced CMOS APS detector. The optical design and the optical coatings are derived from the Extreme Ultraviolet Imaging Telescope (EIT) operating on-board SOHO since 1995 [1]. It has been adapted for a single wavelength telescope with off-axis optics. It allows to use smaller optics and filters, with simple internal baffles avoiding external protruding parts. The superpolished optics will receive a multilayer coating that provides spectral selection centred on 19.5 nm and EUV reflectivity in normal incidence. This compact design is specifically adapted for accommodation on PROBA-2, where mass and envelope requirements are very stringent The SWAP PROBA-2 program will be an opportunity to demonstrate this new optical concept, while it will also validate space remote sensing with APS detectors, as well as on-board image processing capabilities. On the science outcomes, SWAP will provide solar corona images in the Fe XII line on a baselined 2-min cadence. Observations with this specific wavelength allow detecting phenomena, such as solar flares or ‘EIT-waves’, associated with the early phase of coronal mass ejections. The SWAP data will complement the observations provided by SOHO-EIT, and STEREOSECCHI.
This paper presents predictions of space radiation parameters for four space instruments performed by the Centre Spatial
de Liège (ULg – Belgium); EUI, the Extreme Ultra-violet Instrument, on-board the Solar Orbiter platform; ESIO,
Extreme-UV solar Imager for Operations, and JUDE, the Jupiter system Ultraviolet Dynamics Experiment, which was
proposed for the JUICE platform.
For Solar Orbiter platform, the radiation environment is defined by ESA environmental specification and the
determination of the parameters is done through ray-trace analyses inside the EUI instrument.
For ESIO instrument, the radiation environment of the geostationary orbit is defined through simulations of the trapped
particles flux, the energetic solar protons flux and the galactic cosmic rays flux, taking the ECSS standard for space
environment as a guideline. Then ray-trace analyses inside the instrument are performed to predict the particles fluxes at
the level of the most radiation-sensitive elements of the instrument.
For JUICE, the spacecraft trajectory is built from ephemeris files provided by ESA and the radiation environment is
modeled through simulations by JOSE (Jovian Specification Environment model) then ray-trace analyses inside the
instrument are performed to predict the particles fluxes at the level of the most radiation-sensitive elements of the
instrument.
The Extreme Ultraviolet Imager (EUI) on-board the Solar Orbiter mission will provide full-sun and high-resolution image sequences of the solar atmosphere at selected spectral emission lines in the extreme and vacuum ultraviolet. After the breadboarding and prototyping activities that focused on key technologies, the EUI project has completed the design phase and has started the final manufacturing of the instrument and its validation. The EUI instrument has successfully passed its Critical Design Review (CDR). The process validated the detailed design of the Optical Bench unit and of its sub-units (entrance baffles, doors, mirrors, camera, and filter wheel mechanisms), and of the Electronic Box unit. In the same timeframe, the Structural and Thermal Model (STM) test campaign of the two units have been achieved, and allowed to correlate the associated mathematical models. The lessons learned from STM and the detailed design served as input to release the manufacturing of the Qualification Model (QM) and of the Flight Model (FM). The QM will serve to qualify the instrument units and sub-units, in advance of the FM acceptance tests and final on-ground calibration.
Solar Orbiter EUI instrument was submitted to a high solar flux to correlate the thermal model of the instrument. EUI, the Extreme Ultraviolet Imager, is developed by a European consortium led by the Centre Spatial de Liège for the Solar Orbiter ESA M-class mission. The solar flux that it shall have to withstand will be as high as 13 solar constants when the spacecraft reaches its 0.28AU perihelion. It is essential to verify the thermal design of the instrument, especially the heat evacuation property and to assess the thermo-mechanical behavior of the instrument when submitted to high thermal load. Therefore, a thermal balance test under 13 solar constants was performed on the first model of EUI, the Structural and Thermal Model. The optical analyses and experiments performed to characterize accurately the thermal and divergence parameters of the flux are presented; the set-up of the test, and the correlation with the thermal model performed to deduce the unknown thermal parameters of the instrument and assess its temperature profile under real flight conditions are also presented.
The Solar Orbiter mission will explore the connection between the Sun and its heliosphere, taking advantage of an orbit
approaching the Sun at 0.28 AU. As part of this mission, the Extreme Ultraviolet Imager (EUI) will provide full-sun and
high-resolution image sequences of the solar atmosphere at selected spectral emission lines in the extreme and vacuum
ultraviolet.
To achieve the required scientific performances under the challenging constraints of the Solar Orbiter mission it was
required to further develop existing technologies. As part of this development, and of its maturation of technology
readiness, a set of breadboard and prototypes of critical subsystems have thus been realized to improve the overall
instrument design.
The EUI instrument architecture, its major components and sub-systems are described with their driving constraints and
the expected performances based on the breadboard and prototype results. The instrument verification and qualification
plan will also be discussed. We present the thermal and mechanical model validation, the instrument test campaign with
the structural-thermal model (STM), followed by the other instrument models in advance of the flight instrument
manufacturing and AIT campaign.
The Extreme Ultraviolet Imager (EUI) onboard Solar Orbiter consists of a suite of two high-resolution imagers (HRI)
and one dual-band full Sun imager (FSI) that will provide EUV and Lyman-α images of the solar atmospheric layers
above the photosphere.
The EUI instrument is based on a set of challenging new technologies allowing to reach the scientific objectives and to
cope with the hard space environment of the Solar Orbiter mission.
The mechanical concept of the EUI instrument is based on a common structure supporting the HRI and FSI channels,
and a separated electronic box. A heat rejection baffle system is used to reduce the Sun heat load and provide a first
protection level against the solar disk straylight. The spectral bands are selected by thin filters and multilayer mirror
coatings. The detectors are 10μm pitch back illuminated CMOS Active Pixel Sensors (APS), best suited for the EUI
science requirements and radiation hardness.
This paper presents the EUI instrument concept and its major sub-systems. The current developments of the instrument
technologies are also summarized.
The JWST Mid-Infrared Instrument (MIRI) is designed to meet the JWST science requirements for mid-IR capabilities
and includes an Imager MIRIM provided by CEA (France). A double-prism assembly (DPA) allows MIRIM to perform
low-resolution spectroscopy. The MIRIM DPA shall meet a number of challenging requirements in terms of optical and
mechanical constraints, especially severe optical tolerances, limited envelope and very high vibration loads.
The University of Cologne (Germany) and the Centre Spatial de Liege (Belgium) are responsible for design,
manufacturing, integration, and testing of the prism assembly. A companion paper (Fischer et al. 2008) is presenting the
science drivers and mechanical design of the DPA, while this paper is focusing on optical manufacturing and overall
verification processes.
The first part of this paper describes the manufacturing of Zinc-sulphide and Germanium prisms and techniques to ensure
an accurate positioning of the prisms in their holder. (1) The delicate manufacturing of Ge and ZnS materials and (2) the
severe specifications on the bearing and optical surfaces flatness and the tolerance on the prism optical angles make this
process innovating. The specifications verification is carried out using mechanical and optical measurements; the
implemented techniques are described in this paper.
The second part concerns the qualification program of the double-prism assembly, including the prisms, the holder and
the prisms anti-reflective coatings qualification. Both predictions and actual test results are shown.
We present how it is achieved to mount a double prism in the filter wheel of MIRIM - the imager of JWST's Mid
Infrared Instrument. In order to cope with the extreme conditions of the prisms' surroundings, the low resolution
double prism assembly (LRSDPA) design makes high demands on manufacturing accuracy. The design and the
manufacturing of the mechanical parts are presented here, while 'Manufacturing and verification of ZnS and Ge
prisms for the JWST MIRI imager' are described in a second paper [1]. We also give insights on the astronomical
possibilities of a sensitive MIR spectrometer. Low resolution prism spectroscopy in the wavelength range from
5-10 microns will allow to spectroscopically determine redshifts of objects close to/at the re-ionization phase of
the universe.
MIRI, the Mid-InfraRed Instrument, is one of the 4 instruments currently under development for the NASA/ESA
James Webb Space Telescope. Together with the US, MIRI is built by a consortium of 28 European institutes
under the lead-management of ESA. The instrument consists of two main modules, a spectroscopic and an
imaging part. The imager will allow imaging, coronography and low resolution spectroscopy. The latter mode
will use a ZnS-Ge-double-prism assembly as dispersive element.
In this contribution, we present the design concept for the mounting of this double prism assembly which places
the prisms into the optical path of the imager via an interface to the imager's filterwheel. Despite the very
limited available space in the filterwheel and the high weight of the prisms (in comparison to the other filters
in the filterwheel), the kinematic mounting of the individual prisms guarantees exact placement with smallest
possible induced forces into the prisms. The here presented design of the development model of the double prism
assembly is based upon GEM calculation. Experimental thermal and vibrational tests will be performed by the
time of this conference.
The MAGRITTE telescopes are part of the SHARPP instrument suite, part of the Solar Dynamics Observatory (SDO), a NASA spacecraft to be launched in a geostationnary orbit in 2007. The MAGRITTE instrument package will provide high resolution images of the solar corona at high temporal frequency simultaneously in 5 EUV and in Ly-α narrow bandpasses. The 1.4 R0 MAGRITTE common field of view complements the other SHARPP instruments, as well as its spectral coverage with 6 narrow bandpasses located within the 19.5 to 120 nm interval. The key challenges of the MAGRITTE instrument are a high angular resolution (0.66 arcsec/pixel) with a high responsivity (exposure times smaller than 8 sec), combined with restricted spacecraft resources. The design of MAGRITTE is based on a high performance off-axis Ritchey-Chretien optical system combined with a large detector (4 K x 4 K, 12 µm pixel). The tight pointing stability performance of 1.2 arcsec over the image exposure time requires an active image motion control, using pointing information of a Guide Telescope, to compensate low frequency boresight variations produced by spacecraft jitter. The thermomechanical design and the mirror polishing are highly critical issues in the instrument design. This paper presents the MAGRITTE design concept with the expected performances based on a realistic error budget. The mirror polishing concept and performances are discussed.
The Solar Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory will characterize the dynamical evolution of the solar plasma from the chromosphere to the corona, and will follow the connection of plasma dynamics with magnetic activity throughout the solar atmosphere. The AIA consists of 7 high-resolution imaging telescopes in the following spectral bandpasses: 1215Å. Ly-a, 304 Å He II, 629 Å OV, 465 Å Ne VII, 195 Å Fe XII (includes Fe XXIV), 284 Å Fe XV, and 335 Å Fe XVI. The telescopes are grouped by instrumental approach: the MAGRITTE Filtergraphs (R. MAGRITTE, famous 20th Century Belgian Surrealistic Artist), five multilayer EUV channels with bandpasses ranging from 195 to 1216 Å, and the SPECTRE Spectroheliograph with one soft-EUV channel at OV 629 Å. They will be simultaneously operated with a 10-second imaging cadence. These two instruments, the electronic boxes and two redundant Guide Telescopes (GT) constitute the AIA suite. They will be mounted and coaligned on a dedicated common optical bench. The GTs will provide pointing jitter information to the whole SHARPP assembly. This paper presents the selected technologies, the different challenges, the trade-offs to be made in phase A, and the model philosophy. From a scientific viewpoint, the unique combination high temporal and spatial resolutions with the simultaneous multi-channel capability will allow MAGRITTE / SPECTRE to explore new domains in the dynamics of the solar atmosphere, in particular the fast small-scale phenomena. We show how the spectral channels of the different instruments were derived to fulfill the AIA scientific objectives, and we outline how this imager array will address key science issues, like the transition region and coronal waves or flare precursors, in coordination with other SDO experiments. We finally describe the real-time solar monitoring products that will be made available for space-weather forecasting applications.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.