A Journey to the Oort Cloud, Where Comets Are Born
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.
Andrew Fraknoi is chair of the Astronomy Department at Foothill College in Los Altos, California.