Session 8 - Space Systems Engineering: Space Climate Modelling and the Effects of Severe Space Weather Events

Eamonn Daly (European Space Agency); Richard Horne (British Antarctic Survey); Daniel Heynderickx (DH Consultancy); Hugh Evans (European Space Agency); Dave Pitchford (SES), Nigel Meredith (British Antarctic Survey); F. Lei (RadMod Research)
Wednesday 29/11, 9:45 - 13:00
Delvaux


KEYWORDS - Radiation belts; extreme events; spacecraft; radiation effects; charging; space climate

Satellite engineering standards include methods for specification of space climate (e.g. radiation and plasma environments, and their variability). These should be updated to reflect new data analyses and improved. understanding. This session will discuss space climate model improvements, particularly related to extreme (Carrington-type) events, and also those resulting from improved analyses of radiation belts from LEO to GEO. Effects on space systems, and their trends, will also be presented.

Poster Viewing
From Monday noon to Wednesday morning

Talks
Wednesday November 29, 09:45 - 11:00, Delvaux
Wednesday November 29, 11:45 - 13:00, Delvaux

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Talks : Time schedule

Wednesday November 29, 09:45 - 11:00, Delvaux

09:45	Methodology and Data Sources for Assessing Extreme Space Weather Events	Parker, L et al.	Oral
	Linda Neergaard Parker, Joseph I. Minow
	USRA, NASA
	Radiation and spacecraft charging are potential threats to both manned and robotic missions. The U.S. Space Weather Action Plan (SWAP) made initial assessments of 1 in 100 benchmarks for high energy galactic cosmic ray, solar energetic particles, and trapped radiation belt particle environments of concern for radiation dose and single event effects in humans and hardware for the near-Earth environment. However, the team chose to defer work on the lower energy charged particle environments needed to evaluate the threat of charging to critical space infrastructure operating within the near-Earth ionizing radiation environments. Therefore, an initial set of 1 in 100 year spacecraft charging environment benchmarks remains to be defined to meet the SWAP goals. Space environment assessments for lunar travel and travel to other planets, such as Mars were not included in the SWAP requirements. This presentation will discuss the available data sources and a methodology to assess the 1 in 100 year extreme space weather events that drive radiation, surface and internal charging threats to spacecraft and crew. Environments to be considered are the hot plasmas in the outer magnetosphere during geomagnetic storms, relativistic electrons in the outer radiation belt, energetic auroral electrons in low Earth orbit at high latitudes, and interplanetary high energy particles.
10:05	Extreme relativistic electron fluxes in the Earth's outer radiation belt: Analysis of INTEGRAL IREM data	Meredith, N et al.	Oral
	Nigel P. Meredith[1], Richard B. Horne[1], Ingmar Sandberg[2,3], Constantinos Papadimitriou[2] and Hugh D. R. Evans[4]
	[1]British Antarctic Survey, Cambridge, UK; [2]Space Applications and Research Consultancy, Athens, Greece; [3]Institute of Accelerating Systems and Applications, Athens, Greece; [4]European Space Research and Technology Centre, The Netherlands
	Relativistic electrons (E > 500 keV) cause internal charging and are an important space weather hazard. To assess the vulnerability of the satellite fleet to these so-called ''killer'' electrons it is essential to estimate reasonable worst cases, and, in particular, to estimate the flux levels that may be reached once in 10 and once in 100 years. In this study we perform an extreme value analysis of the relativistic electron fluxes in the Earth's outer radiation belt as a function of energy and L*. We use data from the Radiation Environment Monitor (IREM) on board the International Gamma Ray Astrophysical Laboratory (INTEGRAL) spacecraft from 17 October 2002 to 31 December 2016. The 1 in 10 year flux at L* = 4.5, representative of equatorial medium Earth orbit, decreases with increasing energy ranging from 1.36x10^7 cm^-2s^-1sr^-1MeV^-1 at E = 0.69 MeV to 5.34x10^5 cm^-2s^-1sr^-1MeV^-1 at E = 2.05 MeV. The 1 in 100 year flux at L* = 4.5 is generally a factor of 1.1 to 1.2 larger than the corresponding 1 in 10 year flux. The 1 in 10 year flux at L* = 6.0, representative of geosynchronous orbit, decreases with increasing energy ranging from 4.35x10^6 cm^-2s^-1sr^-1MeV^-1 at E = 0.69 MeV to 1.16x10^5 cm^-2s^-1sr^-1MeV^-1 at E = 2.05 MeV. The 1 in 100 year flux at L* = 6.0 is generally a factor of 1.1 to 1.4 larger than the corresponding 1 in 10 year flux. The ratio of the 1 in 10 year flux at L* = 4.5 to that at L* = 6.0 increases with increasing energy ranging from 3.1 at E = 0.69 MeV to 4.6 at E = 2.05 MeV.
10:20	Extreme events in the Earth’s electron radiation belts	Glauert, S et al.	Oral
	Sarah A Glauert, Richard B. Horne, Nigel P. Meredith
	British Antarctic Survey, Cambridge, UK
	In the Earth’s outer electron radiation belt, the high energy (> ~500 keV) electron flux can be very dynamic and has been observed to change by orders of magnitude within a few hours. Since these electrons can cause internal charging in satellites, it is important to understand and quantify the likely worst case fluxes that satellites could encounter. Two different extreme events were studied as part of the EU-FP7 SPACESTORM project; a very large coronal mass ejection (CME) and a period of very high speed solar wind. The BAS Radiation Belt Model (BAS-RBM) has been adapted to model both types of extreme event, and validated by comparing the model results with data for a large event of each type. To achieve a realistic scenario for the extreme CME, data from a CME in July 2012 that missed the Earth but was observed by STEREO-A is used to define the event. The simulations show that the magnetopause is likely to come inside L*=5, the most extreme fluxes occur in MEO, and that the >2 MeV flux at GEO following the event is only comparable to about a 1 in 10 year event. The extreme solar wind stream simulations are defined using a previously published super-posed epoch analysis of 40 high speed stream events. In this case the magnetopause remains at larger L* and the electron flux at MEO and GEO can reach higher levels than those seen with the extreme CME.
10:40	Low energy electron radiation environment for extreme events	Ganushkina, N et al.	Oral
	Natalia Ganushkina[1,2], Stepan Dubyagin[2]
	[1]Finnish Meteorological Institute, Helsinki, Finland; [2]University of Michigan, Ann Arbor, MI, USA
	The electron fluxes at the low (< 200 keV) energies vary significantly with the current activity on the scale of minutes or even shorter. The electrons with these energies do not penetrate deep into the satellite materials but stay near the surface. They can be responsible for surface charging effects which is a serious risk for satellites. We employ our Inner Magnetosphere Particle Transport and Acceleration Model (IMPTAM, imptam.fmi.fi) to investigate the low energy electrons behaviour during extreme conditions. We select two extreme events for our modeling. The first event is July 23-24, 2012 extreme CME event. During this event, extremely fast coronal mass ejection was observed with estimate of its initial speed based on the data of STEREO-B and SOHO coronagraphs of 2500 ±500 km/s. The ejection velocity vector pointed in almost opposite direction from the Earth and, therefore, this event missed the Earth. However, it passed exactly at location of STEREO-A spacecraft, which carried a suite of magnetic field and plasma instruments whose measurements provide the information about physical parameters inside the CME proper. Other parameters were reconstructed and the data were obtained from D. Baker and X. Li (private communication). The second event selected was the observed November 23-24, 2001 severe storm event with fast solar wind. During this event, the solar wind velocity reached 1000 km/s and the Dst index dropped to -230 nT. Measurements from five LANL satellites were available during this event.

Wednesday November 29, 11:45 - 13:00, Delvaux

11:45	Analysis of internal charging processes in extreme MEO electron environment	Paulmier, T et al.	Invited Oral
	T. Paulmier[1], B. Dirassen[1], R. Rey[1], K. Ryden[2], R.Horne[3]
	[1]ONERA- The French Aerospace Lab; [2]Surrey University, Surrey Space Centre; [3]British Antarctic Survey
	The overall objective of this study was to analyse internal charging processes in MEO environment on different systems used on spacecraft. Internal charging analysis includes the evaluation of charging risks on dedicated equipments under representative irradiation conditions and the detection of any possible electrostatic discharge occurring on the element. Charging behaviour of dielectric materials in space environment is steered by complex mechanisms due to the dual effect of high energy electrons that induce charge implantation as well as ionisation. These high energy electrons tend therefore to generate electric potential on the irradiated materials but enhance as well the material conductivity through ionisation processes : we speak about radiation induced conductivity (RIC). The specificity of internal charging, in comparison with surface charging issue, is that thick dielectric materials are used in the spacecraft, and that high energy electrons with low fluxes impinge on these materials. The involved capacitance, resistance and relaxation characteristic time are very different in internal charging. The objective was therefore to analyse the phenomenology and physics of internal charging so as to assess risk of charging and discharging on complex systems and in extreme space weather events. This study was divided into two main major tasks : - Characterisation of electric and charging properties of the defined materials and systems : the objective was to assess the conductivity level of the materials. This characterisation step includes extraction of intrinsic bulk conductivity and radiation induced conductivity (RIC), parameters needed for numerical predictions of charging risks. RIC is generated instantaneously during irradiation but can prevail after irradiation shut-down: we speak about delayed RIC (DRIC). The influence of these different conductivities has been assessed on all defined materials so as to be able to predict charging behaviour in very different irradiation conditions. - Characterisation of charging behaviour in representative irradiation conditions and geometries : the objective was to analyse charging kinetics and risk of electrostatic discharges on representative systems (printed circuit board) and materials in representative grounding configuration and electron radiation (behind shielding). This analysis has been performed through experimental tests and through numerical modelling. This study demonstrated that it is important to take into account, in the physics model, the effect of radiation history and electric fields that can steer at great level long term charging behaviour.
12:10	First results from the Timepix radiation monitor in Low Earth Orbit	Gohl, S et al.	Oral
	Stefan Gohl[1], Benedikt Bergmann[2], Stanislav Pospisil[1]
	[1]Institute for Experimental and Applied Physics
	In Low Earth Orbit (LEO) in Space, electronic equipment on board satellites and space crews are exposed to high ionizing radiation levels. To reduce radiation damage and the exposure of astronauts, to improve shielding, and to assess dose levels, it is valuable to know the composition of the radiation fields and particle directions. We present the analysis of data taken by the Space Application of Timepix Radiation Monitor (SATRAM). There, a Timepix detector (300 µm thick silicon sensor, pixel pitch 55 µm, 256 x 256 pixels) is attached to the Proba-V, an Earth observing satellite of the European Space Agency (ESA) from an altitude of 820 km on a sun-synchronous orbit, lauched on May 7, 2013. In a Monte Carlo simulation the angular dependent detector response to electrons (1 MeV – 10 MeV) and protons (10 MeV – 300 MeV) were determined taking into account the shielding due to the detector housing and the satellite. The stopping power spectrum and the pitch angle distribution(s) of trapped particle tracks were extracted from the measured data, corrected for angular dependent detector responses, and compared with the model prediction from the Space Environment Information System (SPENVIS).
12:30	The AE9/AP9 Radiation and Plasma environment models	O'brien, P et al.	Invited Oral
	T.P. O'Brien[1], W.R. Johnston[2], S.L. Huston[3], T.B. Guild[1], Y.-J. Su[2], C. Roth[3], R. Quinn[3]
	[1]The Aerospace Corporation; [2]Air Force Research Lab; [3]Atmospheric and Environmental Research
	The AE9/AP9 climatology models integrate the latest observations and science into a tool satellite designers can use to develop radiation specifications for missions traversing the Earth’s radiation belts. The model covers trapped radiation and plasma from keV to GeV energies. It provides mean and transient environments, with confidence levels to assess margin. The model is under active development, with major updates occurring every one to two years to further address community requirements. The 2017 update, Version 1.5, incorporates new data including energetic proton and electron data sets from NASA's Van Allen Probes mission. We will present an overview of the model as well as a look ahead at upcoming features and improvements.

Posters

1	Environment conditions during the surface-charging anomaly of the two geosynchronous satellites reported: TELSTAR 401 and Galaxy 15	Saiz, E et al.	e-Poster
	Elena Saiz, Antonio Guerrero, Consuelo Cid, Judith Palacios, Yolanda Cerrato
	Space Weather Group, Departamento de Física y Matemáticas, Universidad de Alcalá, Alcalá de Henares, Spain
	As the satellite-dependent community increases, the vulnerability of the environment where spacecraft are immersed has become a major issue, since this environment can be dramatically modified due to enhanced solar activity. Lower-energy electrons (< 40 keV) delivered into the inner magnetosphere during magnetospheric substorms deposit their charge in spacecraft surfaces. In this work we study the only two events reported by Choi et al. (2011) causing electrostatic discharge during 1997-2010: TELSTAR 401 on January 11, 1997 and Galaxy 15 on April 5, 2010. From the magnetospheric plasma data and ground magnetic field variations at mid-latitude observatories we compare space weather conditions at the time of the anomaly to check if similar conditions placed the satellites at increased risk and which interplanetary features could trigger it.
2	The Project “Universat” of the System of Small Satellites for Monitoring of the Space Threats	Popova, E et al.	e-Poster
	E.P. Popova[1], M.I. Panasyuk[1], V.M. Lipunov[1], M. Barthelemy[4], A.A. Belov[1], V.V. Bogomolov[1], A.S. Chepurnov[1], K.S. Gilchenko[1], G.K. Garipov[1], E.S. Gorbovskoii[1], O.S. Grafodatskii[2], B. Escudier[5], A.F.Iyudin[1], V.V. Kalegaev[1], M.A. Kaznacheeva[1], P.A. Klimov[1], V.G. Kornilov[1], A.S. Kubankin[3], N.V. Kuznetsov[1], S.A. Lemeshevskii[2], S.A. Mit'[1], V.I. Osedlo[1], V.L. Petrov[1], M.V.Podsolko[1], A.Yu. Poroikov[1], M. Protassov[4], A.N. Shustova[1], I.A. Rubinshtein[1], K.Yu. Saleev[1], S.I. Svertilov[1], M. Stepanov[5], Ya.A. Shtunder[1], Yu.D. Troitskaya[1], V.I. Tulupov[1], I.V. Yashin[1]
	[1]M.V. Lomonosov Moscow State University, Russia; [2]S.A. Lavochkin Space Corporation, Russia; [3]Belgorod National Research State University, Russia; [4]Centre Spatial Universitaire de Grenoble, France; [5]Institut Supérieur de l'Aéronautique et de l'Espace, France
	D. V. Skobeltsyn Institute of Nuclear Physics of M. V. Lomonosov Moscow State University (SINP MSU) is developing a project “Universat” of a system of small satellites with a mass <50–100 kg for monitoring of the space threats: ionizing space radiation, electromagnetic transient luminous events in the atmosphere, potentially dangerous objects of natural (asteroids, meteoroids) and artificial (space debris) origin, and powerful gamma ray bursts in space. One of the primary tasks for this satellite system is operational (close to “real time”) monitoring of the fluxes of energetic charged particles in the wide range of Earth’s radiation belts. The necessity of such monitoring is explained by the fact, that these fluxes even during geomagnetically quiet conditions experience very high medium- and long-term variations, which can not be described by existing static models of Earth’s radiation belts. Several small spacecraft will be launched into specially selected orbits crossing the wide range of magnetic drift shells at different altitudes; measure fluxes of energetic electrons and protons by multidirectional detectors; and promptly transmit the data to the ground using satellite retranslation systems. In the ground data-center on the basis of these measurements the current distribution of particle fluxes in the wide range of Earth’s radiation belts (possibly up to GEO) will be computed. The end-user will be able to access the data center by the web-interface. Currently the first research stage of this project is being carried out, during which the optimal spacecraft orbits, instrument construction and placement are being determined. The project is open for cooperation. This work was supported by the RFMEFI60717X0175.
3	Solar Particle Events of September 2017: Multi-Spacecraft Observations and Space System Effects	Jiggens, P et al.	e-Poster
	Piers Jiggens[1], Hugh Evans[1], Eamonn Daly[1], T.A. Lisker[1], Stanislav Borisov[2], Thomas Berger[3]
	[1]ESA Space Environments and Effects Section; [2]Université Catholique de Louvain la Neuve; [3]DLR Inst. Space Medicine
	The largest solar X-ray flare seen in 12 years took place on 6th September 2017. This eruption was accompanied by a fast Coronal Mass Ejection (CME) and an associated Solar Particle Event (SPE) at Earth. This was followed by another huge X class flare on Sunday 10th September with another fast CME and a stronger high-energy SPE. These significant events were occurred as the Sun is approaching solar minimum. We display the observations of various instruments, including imagers and several particle detectors. The event was seen in data from ESA’s spacecraft, including Integral, XMM-Newton, Proba-1, Proba-V, Giove-A, AlphaSat and Galileo. An associated Ground Level Event (GLE) was also detected. An interesting feature of the 10 September event was that the energetic protons arrived very quickly following the X-ray flare, implying a very good magnetic field connection to the site despite the flare occurring on the Sun's West limb. The event allowed comparison of SREM data with GOES energetic proton measurements, showing a good agreement between the different instruments. These data were extracted using the ESA Open Data Interface (ODI) and are available to the public via that free tool. Videos made with SDO and SOHO data using the free JHelioviewer software are displayed. Preliminary energetic proton and alpha particle data from the EPT on ESA’s Proba-V satellite are also shown. We use in-situ flux data to derive the cumulative radiation doses from the event and compared them with doses derived for past solar events as seen by GOES. These data show that the event was a large but not exceptional one and that the dose was relatively low (~2 Gy at 4mm shielding) compared to orbits where doses are dominated by the radiation belts. Contacts with some operators indicate limited impact on operating spacecraft although astronauts on the ISS (international Space Station) were warned since exposure to the event at higher ISS latitudes, in low shielding situations could have been hazardous. DLR report that the event was also well recorded by the DOSimetry TELescopes (DOSTELs) mounted at a fixed position inside the Columbus module of the ISS.
4	New integrated pre-processing chain for radiations and internal charging analysis to model time variations impacts on space systems	Champlain, A et al.	p-Poster
	Benjamin Jeanty-Ruard[1], Arnaud Trouche[1], Pierre Sarrailh[2], Giovanni Santin[3], Didier Falguère[2], Amandine Champlain[1], Julien Forest[4]
	[1]Artenum Toulouse; [2]ONERA; [3]ESA/ESTEC; [4]Artenum Paris
	Future missions will be more sensitive to variations of the space environment. An accurate modelling of these effects, especially regarding radiations and internal charging, is then critical. However, models like the sector shielding analysis reached their limits and new approaches are now needed. Furthermore, considering only worst cases is not enough anymore and a more detailed description of mission scenarios should be considered. For radiations, thanks to R&D efforts sustained by ESA/TEC EPS, a set of Monte-Carlo based simulation models, like GRAS, is increasingly used. However, it still suffers of a lack of a user friendly interface, especially for the CAD modelling. Also initiated by ESA, maintained by the SPINE community, SPIS is open-source 3D PIC software dedicated to the modelling of spacecraft-plasma interactions. SPIS has recently been extended to internal charging effects. To drive of such multi-steps modelling chain and consider variable environments remains complex and link models still challenging. A strong R&D effort has been done at Artenum to address these issues by the development of new tools to set up and control GEANT-4 based models. EDGE is a CAD tool able to create, edit and visualize geometries in GDML format. Offering a rich GUI with 3D views, it allows creating, editing and importing geometrical systems, but also assigning material properties. EDGE is also able to import STEP-AP 203/214 files and export GDML models to various CAD and mesh formats. The Radiation Manager is a dedicated WYSIWYG user interface, allowing to fully set-up GEANT-4 simulation kernels, like GRAS, including the geometry, the material attribution, the particle sources and simulation settings, through standard .g4mac scripts. Geometrical supports for scoring can be defined to transfer data to SPIS-IC for internal charging analysis. Thanks to the scripting capabilities issued from SPIS, it is possible to pilot the whole chain according scenarios, where inputs parameters can be dynamically changed or pre-set environments loaded, including various input spectra. From the cumulated doses and charges, internal charging effects can be computed regularly and the critical phases of the mission identified. To evaluate the approach, validation tests have been performed on various space environments and shielding configurations and discussed.
5	Statistical modelling of solar flare extremes	Tsiftsi, T et al.	p-Poster
	Thomai Tsiftsi
	Centro de Ciencias Matematicas, Universidad Nacional Autonoma de Mexico, Morelia, Mexico
	In this work we analyse data from SWPC/NOAA solar flares. In particular, we statistically analyse the peak X-ray flux of solar flare events; for our statistical analysis we employ Extreme Value Theory (EVT) techniques. EVT models the stochastic behaviour of extreme and rare events and estimates the probability of such events happening at future times. Since this requires extrapolation outside the observed levels, EVT can provide a \textbf{rigorous statistical framework} for such an extrapolation. Our goal is to model extreme solar flares with a Generalised Pareto Distribution (GPD) and provide accurate predictions of extreme solar flare fluxes with good \textbf{statistical reliability} for the next solar cycles to come. We expect these results to inform development of military communication networks, continuity of energy distribution, preparation and protection of satellites in orbit around Earth.
6	Extreme value theory for the study of electron fluxes in the radiation belts: Observations from ICARE-NG/CARMEN-1, SAC-D	Lanabere, V et al.	p-Poster
	Vanina Lanabere[1] and Sergio Dasso[1,2,3]
	[1]Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Ciencias de la Atmosfera y los Oceanos; [2]CONICET, Universidad de Buenos Aires, Instituto de Astronomia y Fisica del Espacio; [3]Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Fisica
	Particles in the radiation belt can significantly increase during geomagnetic storms. The electron population in the outer radiation belt can reach energies in a range from some keV to tens of MeV. The increase of fluxes of these energetic particles has a major interest for Space Weather, mainly because the impact on satellites and human activities in space. A detailed knowledge of the maxima energies reached as well as the extreme fluxes and frequencies, is essential for the specific design of satellites and for the development of satellite technologies. The main purpose of the present work is to study the extreme electron fluxes in terrestrial radiation belts, for an energy range between 0.249 MeV and 1.192 MeV, at 660 km of altitude above the Earth surface, using measurements made by the detector ICARE-NG/Carmen-1 on board the polar Argentinean satellite SAC-D. A statistical analysis based on the peaks over threshold approach was implemented for the daily average electron flux. We find that the cumulative daily averaged electron flux measured at SAC-D is likely to have a finite upper limit (1) in the inner boundary of the outer radiation belt for low energy channels and (2) in the outer boundary of the outer radiation belt for electron energies higher than 0.70 MeV.
7	Empirical model of galactic cosmic ray particle fluxes based on the experimental data in solar cycles 21–24	Popova, E et al.	p-Poster
	Elena Popova, Nikolay Kuznetsov, Mikhail Panasyuk, Mikhail Podzolko
	Skobeltsyn Institut of Nuclear Physics, Lomonosov Moscow State University
	A new empirical model are developed for predicting galaxy cosmic rays (GCR) particle fluxes and radiation doses during space missions. The model is based on the data set measured onboard spacecraft and stratospheric balloons from 1970s till 2015. The model describes fluxes of GCR particles with charge z from 1 to 28 and energy from ~80 MeV/nucleon up to 100 GeV/nucleon in the interplanetary space at heliocentric distance ~1 AU as a function of solar activity (averaged sunspot number). This work was supported by the Russian Science Foundation (Grant 16-17-00098).
8	Space Environment Automated Alerts & Anomaly Analysis Assistant (SEA5)	Boblitt, J et al.	p-Poster
	Justin Boblitt[1], Tyler Schiewe[1], Yihua Zheng[1], Maria Kuznetsova[1], M. Leila Mays[1], Stijn Calders[2], Erwin De Donder[2]
	[1]NASA/Goddard Space Flight Center; [2]Royal Belgian Institute for Space Aeronomy, Brussels, Belgium
	The Community Coordinated Modeling Center (CCMC) is developing a Web-based software system, Space Environment Automated Alerts & Anomaly Analysis Assistant (SEA5), that will provide past, present, and predicted space environment information for specific missions, orbits, and user-specified locations throughout the heliosphere, geospace, and on the ground. Existing space weather resources provide global and large-scale environmental information, but presently there are no highly-tailored services that target specific missions, orbits, or locations in space for any given time period. The targeted outcome of this project is to build an extensible software system that provides an unprecedented capability for (1) viewing space environment conditions for specific missions/orbits, (2) providing automated space weather alerts for specific missions/orbits, and (3) assimilating and displaying spacecraft anomaly/impact information. SEA5 will contain a database of extreme events extending over 1 solar cycle, allowing users to analyze observed and modeled space environment conditions at an asset’s location during past extreme events. SEA5 will also be extensible to modeling extreme (Carrington-type) events, allowing users to analyze potential space environment conditions and impacts for specific assets during hypothetical extreme events. To provide additional real-time environmental impact information for missions, we will be collaborating with ESA's SPace ENVironment Information System (SPENVIS) team to run their models remotely and in real-time from the CCMC, disseminating results through SEA5.
9	Statistical study of DMSP surface-charging events over one solar cycle	Meng, X et al.	p-Poster
	Xuejie Meng, Dong Chen, Liqin Shi, Siqing Liu, Shanqiang Chen
	National Space Science Center, Chinese Academy of Sciences, Beijing, China
	High-level surface charging is frequently observed on spacecrafts in auroral region. Beside sunlit condition, ambient plasma density and precipitating electron flux are two main factors that affect the charging-level. It is known that polar satellites can experience more surface-charging events during solar minimum conditions, and the drop of ambient plasma density due to solar UV output may take the responsibility [Anderson, 2012]. However, the frequent occurrence of geomagnetic activities in solar cycle decent years, which results in energetic electron precipitation, may also contribute to the charging events. In this letter, we present a statistical survey of surface charging events recorded by DMSP satellites. The relationship between the charging events and the geomagnetic activity indices, the solar radio flux at 10.7 cm (F10.7 index), and the sunspot number are investigated using 11 years of data. Ruling out the influence of geomagnetic activities, we have specifically considered the effect of plasma density on surface charging frequency in auroral region.
10	Differences and similarities in relativistic electron fluxes dynamics during two large geomagnetic storms in 2015	Kalegaev, V et al.	p-Poster
	Vladimir Kalegaev[1], Natalia Vlasova[1], Evgenia Beresneva[1], Ilya Nazarkov[1], Arnaud Prost[2], Daniel Boscher[3], Angelica Sicard-Piet[3], Vincent Maget[3]
	[1]Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia; [2]ISAE-SUPAERO, Toulouse, France; [3]ONERA, Toulouse, France
	The role of solar wind pressure and interplanetary magnetic field variations in the dynamics of Earth’s outer radiation belt has been under consideration during the last decades. Unfortunately, there is still no consensus on the physical mechanisms that control the loss and acceleration of the magnetospheric relativistic electron fluxes. The modern space weather services can help in resolving of this problem allowing to provide more reliable analysis of data from multiple models and data sources. In this study we compare and contrast some features of relativistic electron flux dynamics during two intense geomagnetic storms in 2015 (17-18 March and 22-23 June), which have similar Dst-variation profiles and amplitudes (~200 nT) but which occurred in different conditions in the interplanetary space. The improved analysis of experimental data from Van Allen Probes (RBSP), GOES, Electro-L, POES, Meteor-M, SAC-D and Jason-2 satellites was combined with calculations from the model A2000 of the magnetosphere and magnetic field measurements on-board RBSP satellites. Multi-point observations at GEO and LEO orbits show dramatic changes in MeV electron populations during the main phase of the magnetic storms. Comparative analysis of data from multiple sources based on MSU Space Monitoring Data Center facilities shows that solar wind and IMF variations are responsible for large-scale magnetospheric current system and magnetic field changes that reveal themselves in the different dynamics of the relativistic electron fluxes during these two major storms in 2015. This research was supported by Russian Science Foundation (Project No 16-17-00098).
11	Variation of high-energy electron’s flux at geostationary orbit and its correlation with space weather characteristics	Protopopov, G et al.	p-Poster
	Vasily S. Anashin[1], Grigory A. Protopopov[1], Igor A. Lyakhov[1], Valentina I. Denisova[2], Alexey V. Tsurgaev[2]
	[1]Branch of JSC URSC- ISDE; [2]Fiodorov Institute of Applyed Geophysics
	The analysis of flight data is presented in the paper. The flight data are electron fluxes with different energies which are measured by Electro-L spectrometers in geostationary orbit. The fluxes for two energy values are considered – more than 0.2 MeV and more than 1 MeV. Analogous data for 0.8 MeV and 2 MeV from GOES are taken account too. Annual variations of electron’s flux are shown and discussed. We observe a noticeable variation (in 3 times) of annual electron flux values. It should be pointed that minimum electron flux is observed in 2014 with high solar activity. The analysis results and statistics of flux variation and space weather characteristics (solar activity, geomagnetic indexes, geomagnetic storms) will be presented in the paper. Also we compare annual variation and average value of electron fluxes with values which are calculated using different charge particle’s models such as AE8, AE9, IGE 2006 and etc.
12	Long-term modeling of the ring current and radiation belt electron dynamics with the VERB-4D code	Aseev, N et al.	p-Poster
	Nikita Aseev[1,2], Yuri Shprits[1,2,3], Alexander Drozdov[3], Adam Kellerman[3], Dedong Wang[1]
	[1]GFZ German Research Centre for Geosciences, Potsdam, Germany; [2]Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany; [3]University of California, Los Angeles, CA, USA
	Harsh near-Earth ring current and radiation belt regions impose a number of challenges to humanity, such as radiation exposure on crew and passengers of high-latitude aircraft flights, negative effects on ground-based power grids, or communication disruption and even breakdown of satellites operating in the very heart of the plasma environments. For this reason, it is extremely important to understand the physics behind these vast charge particle systems and be able to predict possible consequences of geomagnetic storms. In this work, we present the results of long-term simulations of ring current and radiation belt electron dynamics using the four-dimensional Versatile Electron Radiation Belt (VERB-4D) code. The code takes into account convective transport of electrons, which provide the source population for the environments we study, and diffusion processes leading to particle loss and acceleration. Rather than focusing on particular storms, we consider periods of several hundred days comprising a number of geomagnetic storms. This approach allows us to grasp the physics behind the ring current and radiation belt systems during a rich set of geomagnetic conditions and validate existing models and approaches. We compare the results of simulations to data and demonstrate that the code is capable of reproducing the dynamics of electrons from keV to several MeV energies.
13	Extreme Events and Extreme Energies	Shprits, Y et al.	p-Poster
	Yuri Shprits[1,2]
	[1]GFZ; [2]UCLA
	We present simulations of Radiation Belt dynamics during the Halloween storms and the Carrington-type super storm. We show that Carrington-type superstorm is capable of accelerating electrons in the inner belt where they can persist for year after the storm. We also discuss the dynamics of the ultra-relativistic electrons and show that different physical processes determine the dynamics of the belts at these energies.
14	Radiation hazards and mitigation for M5 ESCAPE	De keyser, J et al.	p-Poster
	Johan De Keyser[1], Iannis Dandouras[2], Masatoshi Yamauchi[3], Henri Rème[2], Octav Marghitu[4], Ioannis Daglis[5], Antonis Paschalis[5] and the M5 ESCAPE proposal team
	[1]Royal Belgian Institute for Space Aeronomy, Brussels, Belgium; [2]Institut de Recherche en Astrophysique et Planétologie, Toulouse, France; [3]Swedish Institute of Space Physics (IRF), Kiruna, Sweden; [4]Institute for Space Sciences, Bucharest-Magurele, Romania; [5]University of Athens, Greece
	ESCAPE is a mission proposal for the ESA Cosmic Vision M5 slot that aims at measuring the escape of atmospheric species – notably oxygen and nitrogen-bearing ions and neutrals – from the Earth’s atmosphere. ESCAPE will examine particle escape by performing in situ measurements while simultaneously providing remote sensing observations of the ionosphere at the conjugate magnetic foot point. The ESCAPE orbit has a high-inclination (> 80°) with perigee and apogee at ~500 km x 33000 km altitudes (~10 hr orbital period) to cover the polar cap, inner magnetosphere, exosphere, and topside ionosphere at all local times. Latitudinal drift of the apogee allows coverage of all altitudes in the polar cap. The high-inclination orbit optimises geomagnetically conjugate observations with the EISCAT_3D ground-based radar facility over northern Europe. We present a radiation environment study for this mission. Since the orbit is located well inside the magnetosphere, it is not surprising that the radiation environment is strongly driven by the radiation belts. For the initial high inclination orbit that is envisaged with a perigee above one pole and the apogee above the other, there is a balanced exposure to the radiation belts during the in- and outbound legs of the orbit. While the perigee altitude does not matter much, lowering the apogee altitude leads to a reduction in the total ionizing dose as the orbit then does not traverse the core of the radiation belts. The argument of perigee changes as the orbit evolves with time, so that deeper traversals of the radiation belts will occur. This study shows that ESCAPE will experience total ionizing doses of maximum 40 krad behind 5 mm Aluminum shielding over its 3-year nominal lifetime. This is an important dose, but not unexpected in view of the spacecraft orbit in the inner magnetosphere. The larger part of the radiation dose is due to the trapped electrons; shielding is therefore rather effective. Of considerable importance for the mission is the Single Event Upset rate. While passing the radiation belts, the MeV particles add background noise to the measurements and may degrade the detectors. ESCAPE therefore plans to switch off most of its instruments in the inner belt, and some of them even in the outer belt. This can be pre-programmed for the inner radiation belt, while the outer radiation belt is too dynamic so that a strategy has been chosen based on real-time monitoring of the particle flux by the energetic ion instrument that is comprised in the payload suite. Such a dynamic on-board approach protects the mission against the adverse effects of severe space weather events.
15	PROBA-V/EPT data products for improved LEO radiation belt understanding	Borisov, S et al.	p-Poster
	Stanislav Borisov, Sylvie Benck and Mathias Cyamukungu
	Center for Space Radiations, Earth and Life Institute, Université catholique de Louvain, (UCL/CSR), Place Louis Pasteur, 3, B-1348 Louvain-la-Neuve, Belgium
	The satellite PROBA-V was launched on 7th May 2013 onto a Low Earth Orbit of 820 km altitude and 98.7° inclination. The Energetic Particle Telescope accommodated on PROBA-V provides uncontaminated fluxes of electrons (0.5–8 MeV), protons (9.5–300 MeV) and alpha-particles (38–1200 MeV). The data products derived from the PROBA-V/EPT measurements include, among others, time series of particle fluxes, weekly flux world maps, static radiation model and characteristics of the radiation belt dynamics. The data quality is achieved not only through the operation principle of the instrument but also from the data analysis and cross-validation processes. This poster presentation will focus on the main features of PROBA-V/EPT data products providing information on their properties and on some ongoing scientific studies based on these data.