The Spitzer Space Telescope took a good, hard look at Comet ISON on June 13, and the results are in. The infrared observations show a steady stream of carbon dioxide and dust flowing away from the comet in a tail over 186,000 miles long.
Does this mean much for the comet's appearance as it comes into sight from Earth? Not really -- but we should know more soon as the comet nears the orbit of Mars, and its icy core starts to warm with the heat of the Sun and release water vapor. The strong carbon dioxide presence may, however, be the reason behind the comet's inital detection at such a far distance from Earth.