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By using rockets to inject hundreds of chemical canisters into the
ionosphere, advertisers could create a “dot matrix” light show in near-Earth
space, says the Issledovatlsky Centre in Moscow (WO 99/51068). Canisters that
contain alkaline earth metals such as magnesium, a battery and an ignition
heater are sealed with plugs and fired off into space. The heater melts the
plugs and vaporises the metals to create a “long-lasting” plasma that glows like
a neon lamp.