the Rosetta Mission website and the ESA are sponsoring this weird Ambition space-project pseudo-biopic:
Ambition is a collaboration between Platige Image and ESA. Directed by Tomek Bagiński and starring Aiden Gillen and Aisling Franciosi, Ambition was shot on location in Iceland, and screened on 24 October 2014 during the British Film Institute’s celebration of Sci-Fi: Days of Fear and Wonder, at the Southbank, London.
but, wouldn't 'liquid water' have boiled off during re-entry/impact of these water-laden comets?
ADDITIONAL CONTENT: here's a link to Jakub Mathia's concept art page for the above-mentioned short film, AMBITION.