Stanford's Star Lab plans future of space weather modification.
By directing repetitive pulses of the electron beam downwards along the magnetic field, Banks and Gilchrist  predicted that a structure consisting of a regularly-spaced series of ionized columns would be produced that could be observed from the ground by suitably located radars. Observations of the striated plasma screen, or “picket fence,” would provide information about some of the properties of the local ionospheric plasma as well as the ionization produced by the electron gun. It could also conceivably be used as a diffraction screen for HF/VHF radio transmissions
The picket fence produced in the ionosphere is a form of ionospheric modification, and our work on the topic led us to consider what further forms of ionospheric modification might be produced by energetic particle or photon beams. Support for a study of these concepts in ionospheric modification was provided early in 1986 by AFGL and the research portion of the study concluded at the end of September 1986. We should point out that the study was one of new concepts in ionospheric modification, based on our electron beam work, and thus no effort was directed toward work on ionospheric modification by means of high-powered ground-based incoherent scatter radars, or by other well-established methods such as barium or other similar chemical releases in the ionosphere. 
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