An ambitious one-day mission to observe the potentially dazzling Comet ISON with a telescope dangling from a colossal NASA balloon this weekend has failed due to a mechanical glitch, NASA officials say. The mission, called the Balloon Rapid Response for ISON (BRRISON), lifted off from Fort Sumner, N.M., on Saturday (Sept. 28) in a bid to make telescope observations of Comet ISON — which some scientists have dubbed as a potential "comet of the century" if brightens on its way into the inner solar system. The telescope-toting balloon aimed to observe the comet from the Earth's upper atmosphere in infrared...