(Planetary Blogs) – Mars Express Team:
In movies about the impending end of the world due to a comet impact, one thing is certain: Detecting the comet and computing its orbit are dead easy. The scene starts with a computer screen showing a telescope image of a star field, where we can make out a faint, fuzzy little object that doesn’t quite look as if it belonged there.
A scientist will throw a brief, disinterested glance at the screen and turn away. Then he stops. His eyes go wide and he snaps around to stare at the screen. He’ll call in his colleagues. Computer programs are started, and people frantically hack away at keyboards. In no time at all, they will have identified the fuzzy blob as a comet that is hurtling in from the frozen recesses of space.
What’s more, in no time at all, they will have determined the comet’s trajectory and they can categorically state that it will hit Earth. A few more frantic calculations and they also know the date and time of impact – Quick, call Bruce Willis!
Neat. But does it really work like that? …
planetary…2014/0312-how
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