ESA'S SPACE ENVIRONMENT INFORMATION SYSTEM (SPENVIS): A WEB-BASED TOOL FOR ASSESSING ENVIRONMENTAL EFFECTS IN SPACECRAFT SYSTEMS D. Heynderickx, B. Quaghebeur, J. Wera BIRA, Ringlaan 3, B-1180 Brussel, Belgium

Overview Overview of space environment and effects Description of SPENVIS Architecture Models and tools Ongoing and future extensions and upgrades Commercial break Demonstration

What is SPENVIS? WWW based interface to models of the space environment and its effects on spacecraft and components: radiation environment dose, NIEL, SEUs, solar cell degradation spacecraft charging magnetic fields atmosphere and ionosphere meteoroids and debris solar irradiance, … Models are run over spacecraft trajectories or coordinate grids Access to satellite data sets and geomagnetic indices On-line help and extensive background information Results in textual, tabular and graphical form

User Community Intended usage: spacecraft engineering scientific educational support Currently about 2,000 internationally registered users Listed on NASA’s Technical Standard site Used by major spacecraft industries and universities

SPENVIS Architecture HTML interface which stores input parameters in text files CGI script spawns runs of stand-alone binaries Output from applications has been converted to straightforward ASCII files with standard headers Output files can easily be downloaded and ingested in other applications (e.g. Excell provides direct import of tables in HTML files) Graphics are produced with IDL; this can be replaced by other packages if needed. Ongoing development to move from CGI scripts to php, similar to LAMP/WAMP (Linux/Windows-Apache-MySql-php). Very flexible architecture, easy to maintain and expand. Framework for other applications

Radiation environment Spacecraft orbit generator Runge-Kutta trajectory tracing Parameter input: 6 orbit parameters, pre-defined orbit types (heliosynchronous, GEO), Two Line Elements Trajectory file uploads Environment models trapped protons (including anisotropy) and electrons solar ions cosmic ray ions (GCR, ACR) Geomagnetic shielding for SEPs and CRs

Radiation effects Radiation effect models ionizing dose non-ionizing dose solar cell degradation: damage equivalent electron fluence for different cell type single event upsets Mulassis: Geant4 Monte Carlo code for shielding analysis

Radiation effects Sector analysis tool Basic building blocks (sphere, box, cylinder) to construct 3D model of satellite system VRML view of geometry 1D and 3D shielding distributions can be folded with flux and dose modelsfolded

Magnetic Field Orbital and grid version Field models: internal: IGRF/DGRF external: Mead-Fairfield, Olson-Pfitzer quiet and dynamic, Tsyganenko 87/89/96/01/04, Ostapenko-Maltsev, Alexeev (ISO draft standard) Drift shell tracing Used for trapped particle models (automatic selection of appropriate models) and geomagnetic cut-off calculations Fortran library:

Atmosphere and Ionosphere Models: NRLMSISE-00, MET V2, DTM, IRI-90, HWM Evaluation over spacecraft orbit: density, flux, and fluence of atmospheric or ionospheric constituents on an oriented surface along an orbit erosion depths for atomic oxygen Over coordinate grids

Spacecraft Charging Data sets: GORIZONT/ADIPE, CRRES/LEPA LEOPOLD: Environment parameters as a function of altitude DICTAT: internal deep dielectric charging FLUMIC trapped electron model Cylindrical and planar configurations Estimate of electrical breakdown and suggestions for design improvement SOLARC: interaction of solar array and spacecraft with plasma environment EQUIPOT: analysis of spacecraft surface charging Simple isolated patch on conducting sphere model Includes major current systems Extended with Katz secondary electron model

Meteoroids and Debris Flux as a function of mass or diameter Grün meteoroid model Debris models: NASA-90 NASA-96 Impact risk analysis Critical impacting particle diameter derived from particle/wall interaction model Probability of puncture Velocity distributions

Other Models and Tools Interface to data bases: satellite data: GOES /SEM, ISEE-1/WIM, ISEE-2/KED, Meteosat-3/SEM-2, STRV-1B/REM, CRRES/MEA, SAMPEX/PET, UARS/PEM, AZUR/EI-88, MIR/REM magnetic and solar indices and parameters format: CDF (ISTP/IACG guidelines) with IDL interface and plotting library Links to and from ECSS-E standard Visualization of coordinate transformations Solar irradiance Geomagnetic cut-off maps

Ongoing and future extensions to SPENVIS Upgrade of the orbit generator: new trajectory types (hyperbolic, parabolic, interplanetary, manoeuvres) Implementation of new environment models (SEP, CR, …) Implementation of new methods for solar cell degradation studies: direct NIEL, SAVANT Upgrade of NIEL calculations (electron and neutron NIEL, extensions to Mulassis) Extension of SEU module to new devices Upgrade of the sector analysis tool: more shapes, stand-alone geometry interface, interface to Geant4 geometry definition Interface to Geant4 GRAS code: advanced toolkit for shielding simulations Interface with external codes and tools (SIREST)

New interface in PHP The SPENVIS 5.0 interface will be completely written in PHP. Object oriented Well documented Easy to maintain or modify Easy to extend Easy to use without knowing all the implementation details

For the users Updated layout Better navigation possibilities including an expandable navigation menu on the left Easier to work with

For the developers More flexible environment Object-oriented script with PHP classes that allow running models and making plots Layout template that includes the expandable navigation menu on the left

Currently implemented interfaces Spacecraft trajectories (SAPRE) Coordinate grid generator (GRID) Trapped Radiation Models Proton Models AP-8 (developed by NSSDC) CRRESPRO (developed by Air Force Research Lab) SAMPEX/PET PSB97 (developed by BIRA) Electron Models AE-8 (developed by NSSDC) CRRESELE (developed by Air Force Research Lab) AE-8 MIN Update ESA-SEE1 (developed by A.L. Vampola)

Commercial break SPENVIS is available at Use of the Web service is free, but needs registration Concept of ‘advanced’ users has been introduced: additional control on input parameters and model runs for selected users; this is one option for future commercialisation Commercial licences for PC Windows and Linux can be purchased One more GSTP contract extension has been approved, but this will be the final one; afterwards, SPENVIS will have to be self-supporting. SPENVIS is linked with ECSS E standard on space environment, and will be linked with new standards on radiation effects and spacecraft charging