Electric solar wind sail applications overview

We analyse the potential of the electric solar wind sail for solar system space missions. Applications studied include fly-by missions to terrestrial planets (Venus, Mars and Phobos, Mercury) and asteroids, missions based on non-Keplerian orbits (orbits that can be maintained only by applying continuous propulsive force), one-way boosting to outer solar system, off-Lagrange point space weather forecasting and low-cost impactor probes for added science value to other missions. We also discuss the generic idea of data clippers (returning large volumes of high resolution scientific data from distant targets packed in memory chips) and possible exploitation of asteroid resources. Possible orbits were estimated by orbit calculations assuming circular and coplanar orbits for planets. Some particular challenge areas requiring further research work and related to some more ambitious mission scenarios are also identified and discussed.Comment: 18 pages, 3 figures, accepted for publication in ESTCube-1 special issue of Proceedings of the Estonian Academy of Science

ESTCube-1 satelliidi raadiomajakas

ESTCube-1 shall be the first Estonian satellite to be launched in 2012. The mission has innovative scientific and educational objectives. The goal of ESTCube-1 satellite is to successfully deploy a single 10 meter long Hoytether structure in low Earth orbit using centrifugal force. The successful tether deployment is needed to demonstrate critical technologies for a full-scale Electric Solar Wind Sail (ESAIL) test mission in the future. The concept of ESAIL has potential to become one of the most efficient space propulsion technologies. It is based on the interaction between the positively charged particles in the solar wind with the positively charged tether net deployed from a satellite. Each tether is a four-fold Hoytether structure so it can be made very light but the whole structure shall retain the durability that is needed in a space environment. The concept was proposed by Pekka Janhunen from Finnish Meteorological Institute in 2006. ESTCube-1 is being developed by students from the University of Tartu and Tallinn University of Technology in tight cooperation with international partners from Finland (Finnish Meteorological Institute, University of Helsinki, Jyväskylä University) and Germany (DLR Bremen). ESTCube-1 communications subsystem (COM) is responsible for the communication between a ground station (GS) and the spacecraft. It can receive telecommands from the GS for setting different operating modes and requests to transmit data. There are two different types of downlink transmission modes: LPTM - Low Power Transmission Mode (Beacon) HPTM - High Power Transmission Mode (Data) The beacon is used for tracking the satellite and to get a simple overview of the satellite's status. The beacon data contains a small subset of telemetry data that is transmitted periodically in Morse code. The HPTM is used for transmitting large amounts of mission data. This consists of telemetry data from each subsystem and the experiment data, for example a picture taken by the camera. HPTM is turned on only after receiving a certain telecommand. The main goals of the current work were to: analyze other CubeSat projects beacon implementations; analyze requirements for ESTCube-1 beacon; determine optimal parameters for ESTCube-1 beacon (output power, transmission period, modulation, beacon data, operating frequency); propose a beacon design for ESTCube-1; analyze operational risks of the beacon design; develop beacon radio frequency (RF) electronics prototype; measure the output parameters of the prototype (signal purity, signal strength, on/off signal ratio. The work consists of ten Chapters. In Chapter 4, an overview of other CubeSat projects beacon implementations is given to see different solutions that are currently operational on orbit. Chapter 5 describes ESTCube-1 satellite in more detail with focus on COM subsystem. Chapter 6 analyzes requirements for developing a satellite beacon. Based on that analysis a beacon design is proposed in Chapter 7. Chapters 6 and 7 form the main body of the work. Chapter 8 describes the beacon radio frequency electronics prototype development and measurement analysis. In Chapter 9, the results of this work are discussed and future activities are proposed. In Chapter 10, most important of these results are concluded and the completion of goals is assessed

Electric Solar Wind Sail in tailwind

The Electric Solar Wind Sail (E-sail) is a novelpropulsion concept that enables faster space travel tomany solar system targets. E-sail uses charged solarwind particles as the source of its propulsion. This isachieved by deploying long, conducting and chargedtethers, which get pushed by the solar wind byCoulomb drag [1].E-sail technology is being developed to technicalreadiness level (TRL) 4-5 by the European Union’sSeventh Framework Programme for Research andTechnological Development, EU FP7, in a projectnamed ESAIL (http://www.electric-sailing.fi/fp7).Prototypes of the key parts are to be produced. Thedesign will be scalable so that a real solar winddemonstration mission could be scaled up from them.We review here the latest results of the constantlyevolving E-sail project

Electric Solar Wind Sail in tailwind

The Electric Solar Wind Sail (E-sail) is a novelpropulsion concept that enables faster space travel tomany solar system targets. E-sail uses charged solarwind particles as the source of its propulsion. This isachieved by deploying long, conducting and chargedtethers, which get pushed by the solar wind byCoulomb drag [1].E-sail technology is being developed to technicalreadiness level (TRL) 4-5 by the European Union’sSeventh Framework Programme for Research andTechnological Development, EU FP7, in a projectnamed ESAIL (http://www.electric-sailing.fi/fp7).Prototypes of the key parts are to be produced. Thedesign will be scalable so that a real solar winddemonstration mission could be scaled up from them.We review here the latest results of the constantlyevolving E-sail project