The solar energetic radiation environment is an important consideration for spacecraft design and spacecraft missions planning. To establish the environment specification a probabilistic, statistical model is used. For high confidences and short mission durations, such as those required for manned space missions, a single event often dominates the time series with the vast majority of the flux being delivered in a matter of days. Such extreme events can have catastrophic effects on spacecraft and their crew.

As part of a recent ESA activity the SEPEM (Solar Energetic Particle Environment Modelling) system was created allowing users to define energetic proton environment models and effects as a function of confidence level with a range of distributions and methods which may be applied to carefully processed data. This system has been used to establish the 95% confidence level SEP event for a 9-month manned mission in near-Earth interplanetary space. The energy range has been extrapolated to cover particles up to 1 GeV as these higher energies are very important when considering heavily shielded spacecraft. The environment model output has been compared to the well-known large August 1972 and October 1989 SEP events which are comparable in size to that which the approved SEPEM model predicts. The expected total ionising dose (TID), non-ionising dose (TNID), the peak fluxes behind the shielding and dose in humans have been calculated as a function of shielding thickness have been calculated using GEANT4 tools such as MULASSIS, SSAT and GRAS. We present the results of these studies. The results have been compared to the current ECSS guidelines where appropriate.

Finally this analysis has been performed for the environment determined by an approximated absolute worst-case event thought to be comparable to the infamous 1859 "Carrington Event". This work will allow designers and planners to establish a reasonable baseline for the impact expected as a result of extreme SEP events of importance to human spaceflight and other future missions.

Lev Dorman for Satellite Anomaly Team*. Results of the Satellite Anomaly Project, which aims to improve the methods of safeguarding satellites in the Earth's magnetosphere from the negative effects of the space environment, are presented. Anomaly data from the "Kosmos" series satellites in the period 1971-1999 are combined in one database, together with similar information on other spacecrafts. This database contains, beyond the anomaly information, various characteristics of the space weather: geomagnetic activity indices (Ap, AE and Dst), fluxes and fluencies of electrons and protons at different energies, high energy cosmic ray variations and other solar, interplanetary and solar wind data. A comparative analysis of the distribution of each of these parameters relative to satellite anomalies was carried out for the total number of anomalies (about 6000 events), and separately for high ( 5000 events) and low (about 800 events) altitude orbit satellites. No relation was found between low and high altitude satellite anomalies. Daily numbers of satellite anomalies, averaged by a superposed epoch method around sudden storm commencements and proton event onsets for high (>1500 km) and low (<1500 km) altitude orbits revealed a big difference in a behavior. Satellites were divided on several groups according to the orbital characteristics (altitude and inclination). The relation of satellite anomalies to the environmental parameters was found to be different for various orbits that should be taken into account under developing of the anomaly frequency models. The preliminary anomaly frequency models are presented. We analyze also main space weather factors caused satellite anomalies and develop models for their forecasting (mainly great SEP events and precipitation of "killed" electrons during great magnetic storms).

Keywords: Space weather; Satellite anomalies; Solar and radiation belts energetic particles; Magnetic storms

* Satellite Anomaly Team: L.I. Dorman a,b,*, D. Applbaum a, A.V. Belov b, U. Dai a, E.A. Eroshenko b, N. Iucci c, A.E. Levitin b, M. Parisi c, N.G. Ptitsyna d, L. Pustil'nik a, A. Sternlieb a, M.I. Tyasto d, G. Villoresi c, V.G. Yanke b I. Zukerman a

a Israel Cosmic Ray and Space Weather Center and Emilio Segre_ Observatory, Affiliated to Tel Aviv University, Technion and Israel Space Agency, PO Box 2217, Qazrin 12900, Israel
b IZMIRAN, Russian Academy of Science, Troitsk, Russia
c Dipartimento di Fisica "E. Amaldi", Roma-Tre University, Rome, Italy
d SPb FIZMIRAN, Russian Academy of Science, St. Petersburg, Russia

It is known that the quality of performance of global navigation satellite systems (GNSS) depends significantly on space weather and, in particular, on the ionospheric conditions. Variations of electron density can change propagation speed of radio waves, introducing a propagation delay for signals. Rapid fluctuations of the electron density may cause cycle slip in carrier phase tracking. Very rapid fluctuations in the signal strength, ionospheric scintillations, can result in significant values of positioning error.
The most drastic perturbations in the ionosphere are known to occur during geomagnetic storms. The latter trigger, in particular, occurrence of intensive ionospheric irregularities and of gradients of electron density, and consequently, cause errors in performance of GNSS. In this work, we analyze global distribution of GPS cycle slips and of GPS positioning errors during ionospheric storms of different intensity. For our analysis we used data of GPS receivers from global networks IGS (ftp://garner.ucsd.edu) and UNAVCO (ftp://data-out.unavco.org). The total number of stations varied from 900 to 2000, depending on an event. The cycle slips were calculated from RINEX files for all satellites and for each GPS frequencies L1 and L2. The positioning errors were calculated as standard deviation between the known precise coordinates of a ground-based GPS receiver and coordinates computed by a receiver at each moment of time. Our analysis shows that the total number of GPS slips is higher during stronger ionospheric perturbations. Apart from the global distribution, we estimate regional contribution as well as day-night contribution. We expect that further developments in this direction will increase the possibility to forecast the GPS operation accuracy based on the input geophysical data, such as index of geomagnetic activity Dst and intensity of interplanetary magnetic field at the beginning phase of during geomagnetic storms of different intensity.
The work is partly supported by the French Space Agency (CNES), and partly by the Russian Federation President Grant -2194.2011.5 and by the grant of the Ministry of Education and Science of the Russian Federation (projects 14.740.11.0078 and 16.518.11.7097).

Solar energetic particle events constitute a real threat for electronics on board operating satellites, especially during the maximum activity phase of the solar cycle. In this study, we constructed solar heavy ion worst-hour flux models and evaluated the effect of such strong radiation on electronic components in terms of Single Event Effects (SEE). Our study is performed on an electronic component in geostationary orbit.

First, we constructed worst-hour proton and heavy ion flux models for 10 major Solar Energetic Particle (SEP) events of Solar Cycle 23 using proton measurements from GOES and heavy ion measurements from ACE/SIS. The chosen SEP events are: July 14 2000, November 9 2000, April 15 2001, September 24 2001, November 4 2001, October 28 2003, October 29 2003, January 17 2005, January 20 2005 and December 13 2006. Estimated energy spectra cover energies from 5 MeV to 20 GeV for protons and heavy ions from helium to nickel (Z = 28). ACE/SIS data for 14 ions were processed and bad data were excluded from the study. Worst-hour energy spectrum profiles for the remaining Z≤28 heavy ions were defined by using solar abundance ratios.

To evaluate the effect of such environments on satellite operations in terms of SEE at component level, we used a typical geostationary satellite geometry. We performed a sector analysis calculation to estimate the shielding provided to an electronic component inside an on-board equipment. The output sector analysis file was used to estimate the Linear Energy Transfer (LET) spectrum for each SEP event model. Finally, SEE rates were estimated for each environment model.

Outputs are compared with results obtained using CREME96, the standard model recommended by ECSS for predicting worst-case solar heavy ion fluxes.

The ionosphere can be the largest source of error in GPS positioning and navigation. When GPS signals pass straight through the ionosphere, they suffer a time delay as a result of the presence of so many free electrons. This typically results in positional errors of few meters, which can increase to tens of meters under extreme ionospheric conditions. Amplitude fading and phase scintillation by small scale irregularities in electron density of ionosphere can cause cycle slip or loss of carrier lock in GPS receiver.

Bursts of energy from the Sun on microwave radio frequencies can disrupt GPS signal reception. Solar radio burst can degrade Signal to Noise Ratio (SNR) of receiving GPS signal cause loss of carrier lock in GPS receiver also.

In this paper we investigated how space weather such as ionosphere and solar radio burst can degrade GPS signal reception, and propose mitigation methods for single frequency GPS receiver.

We present an ongoing effort to improve models of the inner and outer radiation belts with European radiation monitor data. Our effort focuses on the slot region, where existing models are still poor. However, the activity covers all radiation belt regions - except for the outer part of the outer radiation belt - in order to address satellite orbits from typical low-altitude polar orbits to the medium earth orbit of the Galileo navigation constellation.

One objective of MAARBLE project ("Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization"), which is being implemented by a consortium of seven institutions (five European, one Canadian and one US) with support from the European Community's Seventh Framework Programme, is to select and collect European and US particle data sets along different orbits to further perform optimal data assimilation with the Salammbô code and a ensemble Kalman filter. A primary list of missions envisaged so far is XMM/ERMD, INTEGRAL/SREM, PROBA-1/SREM, GIOVE-B/SREM, Cluster/RAPID, THEMIS/SST, Polar/CEPPAD and GOES/SEM. When available in the public domain, the instrument response function is collected and provided as well. Particular effort is devoted to SREM data processing using the Singular Value Decomposition technique to derive smooth proton and electron fluxes.
We present here the status of this database where all data sets are standardized into a unique data format following PRBEM international standards.

Data from the EUV imager SWAP and UV/EUV radiometer LYRA on board the PROBA2 spacecraft are regularly affected by space weather conditions along the spacecraft's orbital path. While these effects are generally removed from calibrated data intended for scientific analysis, they provide an interesting opportunity to characterize the evolution near-Earth space environment as the result of changing space weather conditions. Here we present an analysis of these space weather effects on PROBA2 observations and some conclusions about both the long-term evolution of the inner magnetosphere and short-term events driven by the active sun.

Since the satellite was launch on 2 November 2009, the two solar instruments onboard PROBA2 (http://proba2.sidc.be), had to cope with the effects of degradation at various levels. LYRA, a UV-EUV Radiometer, is the most affected, the four channels of its nominal unit being overlaid by polymerized contaminant. SWAP, an EUV imager, was rather impacted by side-effects of the spacecraft temperature evolution. The various degradation processes perturbing SWAP and LYRA are listed and illustrated, as well as the strategies that have been set up to palliate their effects (operational strategies, baking-out, software correction ...).

In the framework of the ONERA/CNES CRATERRE project, two Radiation Belts Activity Indices and one Solar Proton Event Alarm are developed for post events analysis with less than two days of delays. Exploitation of available data in IPODE (Ionising Particle Onera Data base) allows to define two Radiation Belts Activity indices deduced from daily average fluxes at L=4 using POES/SEM2 electron channel >300keV and JASON2/ICARENG electron >1.6MeV fluxes. For both indices, four classes of activity are settled : quiet, active, very active and extreme. In the same way, a Solar Proton Event Alarm is deduced from POES/SEM2 proton channel >75MeV flux measured above the outer edge of the proton radiation belt. Hourly, solar flare flux level is considered relative to a predefined threshold to determine three alarms: no event, small and large events. Both indices and alarm are plotted over the last 30 days Craterre web site and is updated every days.

Solar activity can trigger sporadic bursts of energetic particles in the solar wind and increase the number of high and low energy particles trapped inside the Earth's radiation belts. These cause damage to satellites and are a hazard for manned spaceflight and aviation. They are difficult to predict due to uncertainties over the basic physical processes, and the need to access reliable data in real time.

The SPACECAST project (European Union Framework Programme 7 Project 262468) aims to protect space assets from high and low energy particles in the electron radiation belts and during solar energetic particle events by developing European dynamic modelling and forecasting capabilities.

SPACECAST uses a MySQL database server (using the ESA Open Data Interface under licence) operated by DH Consultancy to collect magnetic indices, solar wind parameters and GOES particle fluxes in near real time, and combines this with web services to distribute the data to model servers at NERC/BAS, ONERA and FMI, where model runs are executed to obtain forecasts of high and low energy electron fluxes in the radiation belts. The model results are collected by the DH Consultancy server, post-processed and displayed on the SPACECAST web site (http://fp7-spacecast.eu/) in the form of panel plots, movies and alerts (including a satellite risk index for GEO deep dielectric charging). All processes are fully automated and run at hourly intervals.

The model outputs and forecasts include the instantaneous and forecast (over 1, 2 and 3 hours) high energy electron flux and daily fluence, and mappings of the low energy electron flux throughout the radiation belts. The forecast products are continuously validated using metrics such as skill score and RMSE plots, which are also displayed on the web site for peer review of the product quality.

During the next phases of the project, modelling of solar energetic protons and a service to calculate radiation effects will be added. In addition, alert services are being defined which can be tailored by registered users.

Atmospheric density models are used in satellite orbit determination and prediction programs to compute the atmospheric drag force, as well as in upper atmosphere studies. They represent temperature and (partial) density as a function of altitude, latitude, local solar time, day-of-year, and parameters related to the state of atmospheric heating due to solar EUV emissions and solar wind. One of the objectives of the Advanced Thermosphere Modelling for Orbit Prediction (ATMOP) project is developing a new semi-empirical thermosphere model that is more accurate than presently available models. DTM2012 is the first model; the second revised model will be delivered in Fall 2013.
DTM2012 is fitted to the full CHAMP high-resolution density data set, as well as GRACE density data for 2003-2010 in particular. High altitude density data as well as the Dynamics Explorer-2 and Atmosphere Explorer A/C/E mass spectrometer data have also been used. GOCE density data, at 255 km altitude, will be assimilated as soon as possible; they have been used in the validation. Daily-mean densities in the 200-500 km altitude range from the Air Force have also been used for validation only.
This presentation will describe the new model and its new interface, and its performance compared to the pre-ATMOP DTM2009, as well as the CIRA reference model for satellite drag computations, JB2008.

The Cluster and Double Star Digital Wave Processor instruments experience radiation induced single event upsets in the memory devices. The rate at which these events occur has been recorded as a function of L value, and over the duration of the two missions. The statistical study shows strong dependence of relative effects upon L values. At low L values the single events upset rate closely follows the flux of the trapped energetic particles. However at high L values any dependence upon L value disappears and the upset rate exhibits a strong correlation with the galactic cosmic ray flux as recorded by a neutron monitor on the ground. Methodology for a mitigation of single upset effects that are based on the forecasting tools are presented.

The paper presents observations of relativistic electron precipitations (REP) on the "Mir" and International Space Station (ISS) obtained by 4 Bulgarian-built instruments flown in 1989-1994, 2001 and 2008-2010. The first data are from the Liulin instrument flown 1989-1994 inside the Russian "Mir" space station. This period, being in high solar activity, is dominated with large number of solar proton events (SPE) and magnetic storms. These conditions generate large number of inner magnetosphere enhancements, including the formation of the "New radiation belt" at low L values after the SPE on 22 March 1991. This feature was observed by us till the middle of 1993. The second period of observations is in May-August 2001 inside the USA laboratory module of the ISS. Next the time profiles of the REP-generated daily fluences and the absorbed doses outside of ISS during the period February 2008 - August 2010 are analyzed in dependence of the daily Ap index and compared with the daily relativistic electron fluence with energies of more than 2 MeV measured by the GOES. The REP in April 2010, being the second largest in GOES history (with a >2 MeV electron fluence event), is specially studied. These long-term observations support the conclusion that REP is common phenomena on manned satellites. REP and the dose rates variations generated by them inside and outside the manned satellites have to be specially studied because of the space radiation risk which they induced to the crew members during extravehicular activities.

The PLASMON FP7-Space (A new, ground based data-assimilative model of the Plasmasphere - a critical contribution to Radiation Belts modeling for Space Weather purposes) project develops a new data assimilative model to provide near real-time monitoring capability of the densities in the Plasmasphere for modelling Space Weather events. The data assimilative modeling is based on two existing global measuring networks, AWDANet measuring VLF whistlers and EMMA measuring ULF FLRs. A third network, AARDDVARK monitors precipitating particles from the Radiation Belts through VLF signal perturbations. The ground based density data are integrated into a data-assimilative model of the Plasmasphere, which is in turn used to compare model predictions on relativistic electron precipitations with measured data.
The expected final model can serve as a basic tool to monitor the local space environment as well as key data for modelling generation and loss of energetic charged particles. The paper describes the latest advances of the project.

The beginning of September 1859 was the occasion of the first and unique observation of a giant solar white light flare, auroral displays were observed at low latitudes and geomagnetic observatories recorded an exceptional storm. The intention of this paper is to review the impact of the event on the telegraphic network as it was described by various authors at the time including Adolphe Quetelet in Brussels. The techniques used by the operators to mitigate the effects will be described. An attempt to quantify the phenomenon will be made in terms of induced currents on the telegraphic lines. The economic consequences at the time will be assessed from a press review.
The potential consequences on current power and communication transmission systems will be analysed using the experience of previous events like the well documented Halloween event of November 2003. The effectiveness of the current countermeasures used to shield electronic circuits against Single Event Upsets caused by cosmic rays or even by a potential belligerent will be compared against the properties of a Carrington like event.