The National Research Council of Canada has announced that Canadian scientists will launch a series of high-altitude sounding rockets from a temporary launching site on the southeast coast of Nova Scotia during the March 7, 1970, total eclipse of the sun. The Canadians will fire four Black Brant III rockets into the upper atmosphere. The first will be fired six minutes before the moon begins to pass in front of the Sun to measure the undisturbed daytime ionization. The other three will be fired at intervals when the sun is more than 80% obscured, a period of maximum change of ionization.