13:45Adventures in ScienceSeries 1Episode 2: Fire in the Sky - CometsBBC Radio 4 Extra Duration: 15 minutes Tue 22nd Apr 2008, 13:45 on BBC Radio 7Ben Silburn investigates the ocean-making power of the galaxy's 'dirty snowballs' from the mysterious Oort Cloud, beyond Pluto.GenresFactualScience & NatureBrandAdventures in ScienceSeriesAdventures in Science: Series 1 Source: BBC Online