comet• Astronomers had accidentally caught a comet in the act of turning into an asteroid.• Viewed from space, the normalprogress of the surveyship was like the passage of a comet.• Sciorra plays a Colorado astronomer who discovers that an approachingcomet has dislodged several asteroids, propelling them toward Earth.• Rourke was the one who was shooting out of her sphere like a trail-blazing comet.• Surprisingly, they were the first comets found from Britain this century.• Other comets have also been seen to break up.• At best, the comet will be visible to us naked-eye types for only a few more weeks.• To extend the parallel, the impact of the comet would also have released large quantities of hard radiation.