Electric sail

An electric sail (also called electric solar wind sail or E-Sail) is a proposed form of spacecraft propulsion using the dynamic pressure of the solar wind as a source of thrust. It creates a "virtual" sail by using small wires to form an electric field that deflects solar wind protons and extracts their momentum. It was invented by Pekka Janhunen from Finland in 2006 at the FMI.

Development history

To test the technology, a new European Union-backed electric sail study project was announced by the FMI in December 2010. The EU funding contribution is 1.7 million euros. Its goal is to build laboratory prototypes of the key components. The E-Sail research project involved five European countries and ended in November 2013. In the EU evaluation, the project got the highest marks in its category. The technology could enable faster and cheaper access to the Solar System, and in the longer run may enable an economic utilisation of asteroid mining. The working principles of the electric sail underwent testing in 2013 on the Estonian ESTCube-1, to be followed in autumn 2015 on the Finnish Aalto-1 nanosatellites.