Electric solar wind sail : Toward test missions

P. Janhunen, P. K. Toivanen, J. Polkko, S. Merikallio, P. Salminen, E. Haeggström, H. Seppänen, R. Kurppa, J. Ukkonen, S. Kiprich, G. Thornell, H. Kratz, L. Richter, O. Krömer, R. Rosta, M. Noorma, J. Envall, S. Lätt, G. Mengali, A. A. Quarta, H. Koivisto, O. Tarvainen, T. Kalvas, J. Kauppinen, A. Nuottajärvi, and A. Obraztsov Finnish Meteorological Institute, Helsinki FIN-00100, Finland SkyTron, Akaa FI-37800, Finland Department of Physics, University of Helsinki, Helsinki FI-00560, Finland National Science Center Kharkov Institute of Physics and Technology, Kharkov UA-61108, Ukraine Ångström Space Technology Center, Uppsala SE-75121, Sweden Utopia Consultancies, Alfter D-53347, Germany German Aerospace Center, Bremen D-28359, Germany University of Tartu, Tartu EE-50090, Estonia Tartu Observatory, Toravere EE-61602, Estonia University of Pisa, Pisa 56122, Italy University of Jyväskylä, FI-40014, Finland University of Eastern Finland at Joensuu, Joensuu FI-80101, Finland Moscow State University, Moscow 119991, Russia