A spacecraft from Earth has left its cosmic backyard and taken its first steps in interstellar space. After streaking through space for nearly 35 years, NASA's robotic Voyager 1 probe finally left the solar system in August 2012, a study published today (Sept. 12) in the journal Science reports. "Voyager has boldly gone where no probe has gone before, marking one of the most significant technological achievements in the annals of the history of science, and as it enters interstellar space, it adds a new chapter in human scientific dreams and endeavors," NASA science chief John Grunsfeld said in...