n p r n e w s Jan 4, 2013 (Talk of the Nation) — The comet ISON,
discovered by two amateur astronomers last year, will zoom past
the Earth next fall. But where did it come from? Astronomer
Andrew Fraknoi says a passing star could have flung the comet
our way from the Oort Cloud, a distant realm of ice chunks at
the outer limits of the solar system. This text will be replaced
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