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.
A Journey To The Oort Cloud, Where Comets Are Born
By editor • Jan 4, 2013
Originally published on January 4, 2013 1:33 pm