Ninth European Space Weather Week
November 5 - 9, 2012, Brussels, Belgium


Session 4A
Spacecraft Operations and Space Weather


Session: Session 4a Spacecraft Operations and Space Weather 
Date: Thursday 8 November 2012
Chair: R. Horne (British Antarctic Survey, UK) & D. Pitchford (SES)
Remarks: 10:30-10:45 Splinter wrap up

10:45-11:30 Coffee Break & Poster Session

12:30-14:00 Lunch


Time   Title
09:00   Overview of space weather impacts on satellites
Ryden, Keith A.
QinetiQ Fellow, UNITED KINGDOM
Our reliance on space infrastructure is growing and its potential vulnerability to space weather is becoming a cause of concern at high levels in government and elsewhere (for example with space insurers), especially in the context of extreme storm events such as the Carrington Event of 1859. However previous experience of space weather does not necessarily lead to us to ‘Armageddon’ scenarios for the global fleet of satellites, not least because of the careful engineering adopted in space projects. On the other hand it is clear that over the years many satellites have suffered space weather-induced anomalies, outages and failures often due to apparently quite minor storm events. This paper will provide an overview of the historical experience of space weather in practical terms, the engineering reasons for problems and failures, the complex interplay with commercial and security interests and will aim to set out some of the key challenges for the future.
09:20   The Space Environment - A satellite manufacturer's perspective
Daniel Tye
Surrey Satellite Technology Limited (SSTL), UNITED KINGDOM
The Space Environment Team at SSTL is responsible for the thermal control and for the radiation assurance of the satellite. Here, the effects of the radiation environment in Space is discussed, along with the mitigation strategies that SSTL employs to ensure the risk posed by radiation is managed to a level commensurate to the many other risks involved in spaceflight.
SSTL is well-known for employing Commercial Off The Shelf (COTS) electronic components in their satellite products. This approach significantly reduces cost and enhances satellite capability, but exposes components to a radiation environment for which they were not designed.
Presented here is an insight into the thought processes, research, testing, and design rules that have enabled SSTL to follow this approach for more than 30 years and 36 satellites - without the premature loss of a satellite through radiation damage.
This is backed up by in-orbit data from equipments and some of the many radiation monitors SSTL is flying that show the effects of radiation events on our subsystems and demonstrate the robustness of this approach through changing circumstances. We will also show some case studies and mission highlights.
09:40   Effects of Solar Activity on ESA's Science and Earth Observation Missions
Volpp, Jurgen
ESA/ESOC, Darmstadt, GERMANY
During the past twenty years ESA launched 16 Science and Earth observation missions. Most of them are controlled from ESOC in Darmstadt, Germany, and are still operational. These missions have a wide range of orbit characteristics: low Earth orbits, Earth bound orbits with high eccentricity between 240 km and 160,000 km altitude, missions at the Lagrange points L1 and L2 and inter-planetary missions. The operational history of the 19 spacecraft involved represents a large pool of data concerning solar activity influencing spacecraft operations.
This presentation reports on solar activity events which had operational impact as they affected the solar arrays, the on-board memories, the star sensors or the communication with the spacecraft. The possibility of counter measures and their required reaction time is discussed.
10:00   Commercial Development of MEO: An Insurance Perspective
Wade, David
Atrium Insurance, UNITED KINGDOM

Medium Earth Orbit (MEO) has primarily been the preserve of military satellites to date but this will change over the next couple of years as new commercial satellite projects start to occupy this region. In 2013 the O3b constellation will be launched. Operating from a orbit of 9000 km, the O3b satellites will be the first commercial satellites to orbit in the slot region. By 2015, it is expected that the first all-electric geosynchronous communication satellite (the Boeing 702SP) will be launched. Whilst the final destination of such satellites will be geosynchronous orbit, the use of electric propulsion for orbit-raising in addition to station-keeping will expose the satellite to the MEO environment for months as opposed to a conventional geosynchronous satellite which would typically complete orbit raising within a few days. Clear commercial advantages exist for all-electric satellites so manufacturers other than Boeing are also expected to propose all-electric satellites as part of their product range in the coming months.
This presentation will provide an overview of developments in the commercial satellite sector that involve the greater use of MEO, consider previous commercial MEO experience and the implications that the prolonged exposure to the MEO environment may have on satellite design. The presentation will finish with an insurers perspective of these developments and an overview of factors that may affect the insurance assessment of such risks.

11:30   Calculation of the Satellite Surface Charging using forecasted low energy Electron Fluxes
Ganushkina, Natalia; Amariutei, Olga
Finnish Meterological Institute, FINLAND

Modern society depends on a variety of technologies that are susceptible to severe disturbances of the ionosphere and of the near-space environment that are driven by the activity of the Sun. Space weather can adversely affect a wide variety of systems including the space assets such as satellites, manned and unmanned space vehicles and launch vehicles with the addition, although not strictly space assets, of high altitude aviation flights. This study proposes a methodology of forecasting low energy electron population for the study of the effects of the surface charging on spacecraft. We use Inner Magnetosphere Particle Transport and Acceleration Model (IMPTAM), developed by Ganushkina et al. [2001, 2005, 2006], which is a tool to model and forecast the behavior of ring current and radiation belts particles in the inner Earth's magnetosphere.

11:50   NASA GSFC Space Weather Center operational Experiences over the past several major solar Events
Zheng, Yihua1; Pulkkinen, A.2; Taktakishvili, A.3; Mays, M. L.4; Lee, H.5; Chulaki, A.6; Kuznetsova, M. M.4; Hesse, M.4
1NASA Goddard Space Flight Center, UNITED STATES;
2NASA/GSFC and CUA, UNITED STATES;
3NASA/GSFC and UMD, UNITED STATES;
4NASA/GSFC, UNITED STATES;
5NASA/GSFC and KMA, UNITED STATES;
6NASA/GSFC and Sigma Space Corp., UNITED STATES

As a sibling organization of the Community Coordinated Modeling Center (CCMC), the NASA GSFC Space Weather Center has been operational since March 2010 (http://swc.gsfc.nasa.gov).

By combining forefront space weather science and models, employing an innovative and configurable dissemination system (iSWA.gsfc.nasa.gov), taking advantage of scientific expertise -- both in-house and from the broader community -- as well as fostering and actively participating in multilateral collaborations both nationally and internationally, NASA/GSFC space weather Center is poised to address NASA's space weather needs (and needs of various partners) and to help enhancing space weather forecasting capabilities collaboratively. With a large number of state-of-the-art physics-based models running in real-time covering the whole space weather domain, it offers predictive capabilities and a comprehensive view of space weather events throughout the solar system. In this presentation, we will share our operational experience over the past several major space weather events and how they affected NASA spacecraft throughout the solar system.

12:10   Variability of Trapped and Transient Radiation Environment on Highly Elliptical high inclination (Molniya) Orbit
Trichtchenko, Larisa1; Nikitina, Lidia2
1NRCan, CANADA;
2Carleton University, Ottawa, CANADA

Our particular interest in analysis of the radiation environment on Molniya orbit has been motivated by the planned Canadian operational communication and weather space mission which would also include operational particle detectors.
Because the meteorological payload would have to sustain such a diverse radiation environment, its detailed statistical analysis based on data will give better representation of in-flight conditions than widely used AE-8, AP-8 models. These models do not always adequately represent environment on Molniya orbit, while improved models, such as AE9/AP9, are not available for users yet.
Here we present results of statistical analysis of dose rate variability on Molniya orbit, based on HEO-3 data, which includes inner-slot-outer radiation belt regions as well as open field lines affected by transient events (solar energetic particles). To explain the possible source of variability, the behaviour of particular energetic particles (protons and electrons) was also analysed when needed.